So, the thing is, I don't know exactly how it works. For example, the mod might have given you experience for dozens of levels in a single use, and that's why it didn't work now, Either the level was already increased in the test you took, or you tried more than once? Before trying again, do a test: click on the level icon at the top and see if you level up instantly, If you level up just by clicking there, it means the mod has already given you enough experience for dozens of levels. In that case, you'll probably have to create a new account, Understand that it's not a ban, I think it's as if you've reached the end of the game, it's broken.. It's possible that in a future game update, these accounts will be restored. I'm not sure, but it's possible. This doesn't happen when upgrading a specific building; it happens between level 70-71.