Welcome to Android Central! What do you mean by "My apps o can't control"?
How much data is being used? Data usage doesn't necessarily mean someone else has control of your phone -- you might have installed an app that is malfunctioning, or perhaps acting maliciously
What settings and permissions seem to be changing? Keep in mind that sometimes, when there's a major update to an app, some of the settings might reset. And with Android 11, permissions can automatically be revoked if the app hasn't been used for a while:
https://www.howtogeek.com/699129/how...r%20each%20app.