problem with Alitalia

Sherry , unfortunately Alitalia has a horrible , and I mean horrible reputatation, so other then not using them, I suggest you try with Delta again, they may not be able to book seats, but they may be able to help you .. I would also try and arrive at airport for flight so that I was first in line when the desk opens, like if they say checkin for flight opens at 5pm for a 7 pm flight , arrive at 4:30 .. so that you are first in line.
good luck, and if you really can't get any help can you cancel and rebook on another airline? Good luck.

Pat, thanks for the perspective... since that's the case, then at least I won't bother continuing to call Alitalia, hoping to get a 'human'. The last one literally started yelling at me... truly a novel experience with a customer service rep. Can't rebook; too late and too expensive; and a supervisor at Delta confirmed they couldn't do it (and even called Alitalia for me, hoping she could help, but they wouldn't work with her either). The flight is at 6:55 AM, and my recollection is that the Florence airport opens late, so it is a zoo for early flights. I'll try at Alitalia desk at CDG, when I arrive in Europe, and if that doesn't work, I'll see if a travel agent in Europe can help.

Maybe you can do an online check-in. For most airlines/routes that is available 24 hours before the flight leaves. And yes, this has to done through the airline that operates the flight. When I fly to Europe I often have two different airlines operating on the different segments. So I go through the online check-in which each airline individually.

Before you get too angry with Alitalia, you have to know that European airlines normally do NOT assign seats before check-in. This is a major difference between flying in the US and Europe. In Europe seat assignment is normally done as part of the check-in process only. There are exceptions, though. Long haul flights usually have advance seat assignment, as do business class. Furthermore, status passengers are often allowed seat assignment before check in. Also, some airlines allow seat assignment for a fee. But for the average economy class passenger: No advance seat assignement on intra Europe flights on the majority of European airlines. This is simply the way it works on this side of the pond.

Maybe you should carry a note from your doctor saying you require an aisle seat just in case you can't get one assigned.

We were able to choose our seats on most of our Alitalia flights this summer (Amsterdam to Milan, Rome to Amsterdam) when we checked in on the web, but from Milan to Naples we were just assigned seats. The flight attendants on board were very nice. The only exit row seat I've ever sat in was on my Alitalia flight in July, and I was re-seated there onboard by a flight attendant to accommodate a separated family. I've had trouble with ticketing when part of my Delta flights are operated by KLM, too (usually headed back), so it's not just Alitalia.

I booked tickets using miles on United, but 3 of the 4 flights are on Luthhansa, so I called United to get seats, but was told to contact Lufthansa, but they did provide the 6 digit Confirmation code for the Lufthansa flights (different than United confirmation code, but was not reflected on our reservation). Then I called Lufthansa and obtained seat assignments. Since then I've been able to use the Lufthanssa confirmation code to log into my reservation on Lufthansa and confirm the seat assignments have not changed.
So call Delta and ask for the Alitalia confirmation code. Then see if the Alitalia code allows you to get into your reservation on their web site to select a seat.