I'll copy my reply from a different topic:
What learning materials have you made use of?
Do you analyze your games with an engine? Do you check your openings against a database after the game is over?
It's possible to get better, but you'll have to learn new things and change old habits.
I play a lot of chess. Mostly online via apps from my phone. For the amount of games I've logged over the last few years one would think I was pretty good however my rating is still likely 980-1300 give or take the streak. I'm not sure what I'm doing wrong or what else I should be doing to improve. Any suggestions or tips? Please help!