Lost all game progress when I got a new iPad

Bought a new iPad (11" pro), had to do a manual transfer, as only my phone showed up in the iCloud restore list. Signed in with my Apple ID on the new iPad, downloaded a few apps (including the 2 games I play most often) and all my data transferred without a hitch. Even played both game for a little while immediately after. Later that night, when I went to play the games again, all of my 2 years + of progress had disappeared, and I was heartbroken. All of my other data -- contacts, music, etc -- transferred with no problem. And I got the Game Center "Welcome Back" banner when I opened the games, so it recognized my ID, but the game was at Level 1, and asking me to enter a username. Can't understand what happened. Is there any hope of getting my progress back?