I am trying to book seat reservations on Eurostar from London to Paris on 22 May 2022 for the 14:31 train.  The Rail Planner App does not list this departure time but the Eurail.com Internet site does. 

Also, the Eurail Internet site shows much HIGHER Seat Reservation costs than the Rail Planner App (for example the 16:22 train reservation is $45.60 including fees for 1st class & is showing $90.40 USD on Eurail.com). The price is almost double?