Justfly is a scam

Sorry for your experience. It was kind of you to try to warn others. It seems that people rarely check these things out in advance, however. Mostly, they look up the company after something bad happens.

I tried to cancel a flight reservation an hour after I made it and
they hit me with the $75 cancellation charge. I was trying to schedule
a flight from Rochester New York to San Francisco and the reservation
was made for Rochester Minnesota.

It's unfortunate but doesn't look like scam material to me.
They do not promise free cancellation within 24 hours in all cases:

https://www.justfly.com/pdf/termsandconditions.pdf

If you find that you must cancel a booking for any reason, please
contact us. We will do all we can to assist you in this process.
However, please be aware that even if your cancellation is allowed and
your booking is thus refundable, it may be subject to an
administrative cancellation fee displayed in the table below plus
additional fees charged by the Airlines and other Travel Service
Provider.

The "table below" lists a $75 fee if a domestic flight cancellation is found to be subject to one. How they determine what is or is not "subject" would have to be explained by Justfly but it's not a 'hidden' fee possibility by any means.

here are some more details:I do except partial responsibility for my problem. Initially I started my search on Kayak with the wrong Rochester. I caught my mistake and corrected it to the right Rochester. And then I saw the just fly ad and clicked on it. It passed my search information through to their website. And it used the wrong Rochester. I should have bought that mistake but I did not. but I believe that when I refreshed my kayak search that information did not get passed through to just fly. They stuck with the Minnesota Rochester.
My point again was that just fly used two different companies whose business is to generate favorable and credible reviews and each company accuses the other of using fake reviews. I think if you look for reviews of those two businesses you'll see a lot of negative comments about them as well. It's a jungle out there.
and you'll see other unhappy customers of just fly in this travel form. I wish I had checked it before I booked.

It's always better to buy directly from the airline's website -- not use a 3rd party. That said, in all fairness, if you had cancelled a non-refundable ticket you bought from an airline's website 1 hour after you made the reservation, you could lose quite a bit of money including no refund whatsoever.

Airlines allow people to cancel for full refund with 24 hours, so the OP would have received a full refund. Sorry you were hit by the fee. It’s underhanded. There are a lot of complaints on line from people trying to deal with this company.
https://www.consumerreports.org/consumerist/all-major-u-s-airlines-offer-free-cancellations-within-24-hours-except-one/

Airlines allow people to cancel for full refund with 24 hours

Ok, I didn't realize that until I just looked it up. The only stipulation is that the date of travel must be at least 7 days after the date of purchase. Otherwise, no refunds.

yes, I actually did book another flight today at the wrong time through United airline. Canceling it was very easy and there was no charge. I swear I saw on justfly the statement free cancellation within 24 hours. And of course when the airline canceled my just fly flight there was no problem. I got all of my money back from the airline reservation. But, justfly got $75 x 2 to perform that service for me which seems outrageous.

This is a company regularly reported on the Trip Advisor Air Travel forum as having shonky tactics. Here is a link to a years' old thread with nearly 1300 replies about poor service.

https://www.tripadvisor.com/ShowTopic-g1-i10702-k8504032-Justfly_com_is_just_a_scam-Air_Travel.html

If you are not going to book directly with an airline do go to the TA Air Travel forum and do a search before you book. There are hundreds of threads on there with complaints about many online travel agencies.

https://www.bbb.org/us/ca/san-francisco/profile/online-travel-agency/justflycom-1116-874140/details#Pattern-of-Complaint

No 'warm n fuzzy' feeling---- for what little consolation it is, you seem to be one of MANY, victimized by their practice.

OP's most recent post supports why most folk here advise--- 'book with the airline'

Always buy directly from the airline.

I talked with the credit card company and they are filing a challenge and they are issuing me a credit. Justfly has three months to respond. if we don't hear anything from them in the next three months, then this will not have cost me anything and I will have gained from the experience. Thank you to everyone who replied.

I don't see a scam here. What I do see is someone using the wrong airport code and not reading closely enough to ensure the information supplied by the purchaser was valid. If you use a company then you agree to the terms of use by that company.