You can change your seats for the London - Paris leg by using the reservation details at https://www.eurostar.com
You might be able to change the TGV reservations at the ticket office in Paris.
If you had asked here before booking those we could have suggested you to not use the direct Paris - Zurich trains, by changing at Mulhouse or Strasbourg the reservations would have been at most €20 each and possibly only €10.
The reservation fees for passholders on the TGVs from France to Switzerland are an absolute joke. These and other International TGV from France are by far the highest seat reservation fees anywhere in Europe.
Even with that, you appear to have paid more than you should, the reservations bought from eurail are €40 and €70 per person respectively, you must have been charged hefty exchange fees.
Do you know the exact seats you want? SNCF by phone MIGHT be able to help for the Paris to Zurich if you have booking reference (normally 6 letters) but it depends on who you are connected to. On a TGV unit there are not many sets of 4 seats around a table called club quatre in first class. There are more on Eurostar. There are seat plans on the man in seat 61 website for both.
If you had asked here before booking those we could have suggested you to not use the direct Paris - Zurich trains, by changing at Mulhouse or Strasbourg the reservations would have been at most €20 each and possibly only €10.
I wish I had done that; am I able to cancel Paris to Zurich reservation and get a refund. I am travelling next month on Friday October 7 to Zurich.
By the way 253 is reservation for three people in Canadian dollars.
You’ll need to ask whoever make the booking for you but I think you’ll lose a lot of money as I believe the cancellation fee is 40% plus 100% of the agent’s fee.
Hello! Unfortunately, our system does nor have insight on availability therefore your seats are allocated according to availability. As per our experience, you can ask the train staff to change seats-if possible.
.