Every time I make a new
DVC reservation, I have to manually take the confirmation number and enter it in to the
MDE app. Some users reservations cross over automatically, but mine never do.
Go into the MDE app.
Click the tab for "my reservations".
If your DVC reservation doesn't appear, click "link a Disney resort reservation" and enter your confirmation number.
Also make sure your ticket media are appearing in the "tickets and passes" section of the "my reservations" tab.
ONLY when both these things are appearing correctly and you are inside sixty days from the first day of your reservation, you can then select your fp+ for each day of that trip.
If all these steps don't work, call in to member services, when you've got more than an hour of free time to waste.
Good luck! PM me if I can help further.