Start here, because it is nearly always this:
**Sign in with the same Google Play Games account (Android) or Apple Game Center account (iPhone) you used before, then restart the game.**
Reinstalling removes what was stored on the phone itself. What was synchronised to your account comes back when you sign in with that same account - and the usual cause of "everything is gone" is being signed in with a different one, often a second Google account on the same phone.
So check which account you are signed in with before anything else.
If the progress still does not come back, write to support with your Player ID. If you do not have it, send whatever you can: your in-game name, roughly what level you had reached, the device you played on, roughly when you last played, and your purchase receipts if you bought anything. Recovery cannot be promised without a Player ID, but that information gives the best chance of finding the account.
