900-1100 Elo on chess.com?
people can be inconsistent with their play, that's normal. People are far more likely to be inconsistent online than otb. People are far more likely to be inconsistent in a casual setting than in a tournament.
People's FIDE rating comes from tournaments, where everyone is at least expected to be focused on chess.
Online, they can be distracted, playing chess to kill time, unfocused, or persists on playing despite knowing they're having a bad day. I do that more often than I'd like to admit.
The same applies to you. When you pull out the phone to play chess, your mind may not be 100% focused on chess. But when you actively go to a club, your mind is already on chess before the game even begins.
1000-1100 range is also a wild mix bag of serious and casual players. It is a level high enough for studying players to spend some time on, but not high enough to be difficult to reach for casual players.
That's normal, please, see my posts here https://www.chess.com/forum/view/general/what-is-the-difference-between-fide-ratings-and-ratings-here