Paris bus experience wth?

Did you insert your ticket into a machine when you boarded the bus?

https://www.ratp.fr/en/how-do-i-use-a-t-ticket-buses-and-trams

To clarify: did you have 10 paper tickets, or a single plastic card?
The paper tickets need to be inserted in the stamping machine, showing a green light. The plastic card needs to be read by the scanner at the entrance, emitting a 'ding' sound.
The paper tickets are valid for 90 minutes on the buses, but NOT twice on the same line, and you cannot use the same ticket for metro + bus.
The bus drivers are not in charge of enforcing ticket validation (for their personal safety), so it is perfectly normal that they didn't say anything.

Silver lining: Paris fines are cheap compared to most other European cities!

So, we only have one ticket per person. We did insert our tickets into the scanner. It had been at least two hours between when we used them coming to our destination and then heading back. It was the same bus number however. I don’t know if a green light showed up after the machine spit the ticket out. So I will pay attention to that next time. The gentleman suggested that we get a 5 day pass, which we might do. Sort of frustrating to pay for a 10 ride card that we can’t use then pay a fine on top of that. ( and while Paris fines may be better than other European cities an extra unexpected 70 euros out for nothing doesn’t feel very good).

You can't use the same ticket when departing a destination that you used when you went there.

“ It had been at least two hours between when we used them coming to our destination and then heading back.”

Does this mean you used the exact same ticket twice? It seems used the same ticket both on your outbound and inbound journey? If that’s the case, the fine is correct. These types of tickets can only be used for 1 single bus ride.

So apparently I didn’t understand how the 10 ride ticket works. I thought 10 rides meant 10 rides. Not 10 rides only in one direction with a specific amount of time between rides. I guess the onus is on me to know these things in advance. In the RS Paris guidebook he mentions the 10 ride ticket but doesn’t specify the limitations, so I didn’t do any more homework on it. Thank you all for clarifying what was a very confusing and frustrating situation.

My guess is that the OP bought one of the few remaining carnets. A carnet is basically a bundle of 10 single tickets. The RATP doesn’t sell carnets of 10 paper tickets any longer, but some resellers like Eurostar still have them. Since these carnets are nothing but 10 single tickets sold in 1 pack and cost €15,50. You can still use the tickets even though the carnet is no longer sold.
Like I said, a carnet consists of 10 single tickets. These tickets are called t+ ticket. The conditions of a t+ ticket can be found here; https://www.ratp.fr/en/titres-et-tarifs/t-tickets

Information about the phasing out of the carnet of 10 paper tickets; https://www.connexionfrance.com/article/French-news/Ile-de-France-starts-phasing-out-paper-Paris-Metro-tickets

@ Dutch_Traveler, I see your point but the OP said that they had a single ticket and not 10 paper tickets so it could not have been an old-school carnet unless Eurostar was doing a total rip off move and selling a single paper ticket as a 10-ride ticket.

@ Stephanie H, The 90-minute and 2-hour rules apply to transfers on the same ticket. It really has nothing to do with your situation. One can transfer freely from line to line for two hours after the first validation on the metro and 90 minutes on the buses and trams. It sounds like you scanned the pass but it did not take. Did you hear the ding when you got on the bus for the return trip?

It doesn't sound like she had a paper ticket from a carnet. I thought those were being phased out in favor of the card, which she describes. If she had a paper ticket from a carnet, it WOULD have to have a validation stamp on it. Every time I've ever seen transit police checking cards (in other cities - I haven't been to Paris since they starting phasing in ride cards), or e-tickets, they have handheld scanners that determine whether or not the card/e-ticket is valid and whether the rider used it to board the bus/train.
I don't understand why a ten-ride ticket loaded onto a card wouldn't work. Unless she was sold a dud by the Eurostar people. You tap the card, it deducts a ride. Unless she tapped the card to begin the ride and it didn't "take", and the transit police DID scan her card and determine that she didn't tap the card to pay for her bus ride.

I'd be interested to know what the transit police did with her card when she handed it to them.

The reason I think the OP bought a carnet of 10 t+ tickets, is because she describes it as “It is a small card with a mag stripe on the back.”. This is exactly how a t+ ticket looks like. A Navigo pass is the same size as a credit card, so most people would use the phrase “credit card sized” to describe it instead of “small card”.
Perhaps the OP can help us by describing the card? I’m going to post a link with the various ticket types available; https://www.ratp.fr/en/titres-et-tarifs
Does your ticket look like the first ticket in this link, or the second?

@ Dutch_traveler, I thought the same thing at first: that it was an old school carnet and Eurostar had sold her a single ticket as a 10-ticket. What a rip off that would be and I decided against that because I hate to think that Eurostar is that incompetent or fraudulent. The OP mentioned scanning the ticket and then the machine spitting the ticket out which is a mash up of how the two tickets are processed. Paper tickets are inserted and spit back out and the cards are scanned. Overall, it is confusing because details matter for us to know or figure out what went wrong. If it was a single paper ticket and I was the OP, I would contact Eurostar and insist on getting my 15.50€ back as well as the amount of the fine. If it was the Navigo Easy, then we have a totally different situation. If it was a paper ticket, then the OP got lucky with the first ride because that ticket was no longer good after the ride from Gare du Nord.

The inserting the ticket into the scanner and the machine spitting it out is why I think the OP doesn’t have a Navigo pass. You can’t insert a Navigo pass into the machine, the machine is too small for that. Therefore the machine also can’t spit it out.
It would help if the OP could describe how the ticket she bought looks like and how many of these tickets she received.

Agreed; let's see if the OP comes back or if they are too busy enjoying a trip to Paris.

or perhaps he/she had used up their tickets already (knowingly or otherwise)

Ahh, @Dutch_traveler, you might be right. The paper tickets did have a stripe on the back. I'll be interested to hear if it was in fact a small paper ticket or a credit-card sized travel card with rides loaded.

I hope she's enjoying her Paris trip, though being fussed at in French and made to pay (or feeling as if she must pay) a 70 Euro fine on the spot, would put a damper on my trip, at least for the day.

Wow, thank you all for your interest and concern. I just finally figured out what happened as I sat down to tally up the last few days of expenses. So while I asked the Eurostar fellow for the 10 day ticket, and thought that’s what I was charged for, I found a receipt for only two single ride ticket! (Forehead smacking gesture here). Because the train was swaying around and I was focusing on not falling over I didn’t actually look at the receipt until tonight. So I feel foolish at being upset for something that was an innocent mistake between the cashier and myself. I now actually have a 5day Navigo card so no more costly fines!! Thank you all for your input 😊

Thanks for reporting back, it makes sense now. However this does mean that the fine was rightfully given to you. Your single ride ticket was no longer valid, and while you didn’t mean to, you were traveling without a valid ticket.
I hope this doesn’t put a damper on your trip and I hope you will enjoy your remaining time in Paris!

Thanks for reporting back. It's good to know that this was just an innocent mistake on the part of Eurostar. My husband rarely checks his receipts and I usually check mine and he teases me about that. I shall share this thread with him. Bon voyage.

Stephanie, I am sorry you had a bad experience when you had tried to do the right thing ! I hope the rest of your trip will go smoothly and you will enjoy Paris.

I was at the Lourve yesterday and also was stopped by officials. They scanned my ticket and it passed whatever they were looking for. I had bought a stack of paper tickets and I have only been using them once. Ie one single one way ride. I bought the paper tickets because my niece had a frightening experience with the pass. She was stopped and threatened with jail because she had not attached a photo to her pass. She did end up paying a fine on the spot but was shaken by the experience.

By the way so far my experience with Paris busses has been not so great. They just don't arrive at the stop or they are 20 to 30 minutes late. The Metro has been more reliable but it is also packed with people. London spoiled me as far as transportation goes.

Wow Cerastez, that’s interesting that you had a similar (but different) experience! The transit police are intense and intimidating! We’ve had about a third of the busses be late- like really late- 10 minutes or more. Today we sat at a stop and the bus was supposed to be there in 6 minutes, then the next time I checked it was 16 minutes. Similar thing happened this evening on a different route. I can understand when it’s super busy and traffic is congested. And yes, the metro is often packed. Kinda hard when you’ve been walking all day and just want to sit down 😊. But hey, first world problems, so I’m not too bothered. Hope you enjoy the rest of your trip!

Dutch traveller, as recently as May the RATP has still been selling the paper packages of 10 individual tickets. There are fewer machines in the Metro where they can be used but every bus we were on had the paper ticket machine.

Shops and other places like Eurostar or Thalys trains are allowed to sell their remaining stock of paper carnets, but paper tickets they will definitely be phased out and replaced by electronic cards. See the article I linked to previously.
The RATP website no longer lists a paper carnet amongst the available ticket types and ticket machines at the metro stations no longer sell them.

Paris is down 25% of its bus drivers, trying to recruit and train new ones, according to the France 2 TV news this evening. The journalists interviewed people trying to get to work and appointments, showed trying to squeeze onto buses, and showed long wait times. This explains the experience reported above.

I don't get being 'shaken' and refusing to use passes because someone violated the clear terms of the pass. Navigo Decouverte passes require photos since they are not transferrable and it is pretty obvious when you buy them and assemble them -- there is this big spot with 'photo' on it to attach the photo. This is not some mysterious assault by a draconian metro police core.

I really appreciate the clarity and good nature of the OP and the kind support offered to her.
I've had my Navigo Pass for about 6 years or so.
I reload it for a week at a time whenever I come to Paris and I made sure that I set it up correctly with a photo when I first bought it.
I have noticed more transit police checking validity on each visit but they have always been polite to me because my pass is valid and I make sure to scan it even on the buses when there is no door control.
Hopefully the OP will not have any more trouble and others reading this will pick up some cues.

Janettravels44, it’s easy enough to get a Navigo without a photo- in fact I’m keeping my fingers crossed we don’t have to show ours because when we went to get them (after the whole ticket debacle) the fellow at the metro station asked for a photo and I said we didn’t have one and he just sold them to us anyway- didn’t say they were legally required or offer us and option to where to get a photo, or tell us to get a single use ticket until we got a photo. Just yesterday I saw a photo booth in a metro station and tried to take one, but it came out too big for the spot on the pass, so I really don’t know how to resolve that issue. In regards to feeling shaken- when someone with badges and very official is screaming in your face in a language you don’t understand it’s pretty easy to feel shaken- just saying.

Janet's response was directed at Ceratez's niece's experience. That's who Ceratez said didn't have a photo and was shaken.

Sometimes these responses get all jumbled and we no longer know what we are reading or writing.

I think the lesson for others reading this and planning to visit any city for the first time is to research what options there are for public transportation, what is required, etc.
Google is very helpful.
In the case of Paris, Parisbytrain.com explains it all. I assume Rick Steves does too in his guidebooks. And then of course, this forum where it’s been explained often.