I think my account was hacked

1. Change your password (if you can't sign in, see I forgot my password).
2. In Settings → Account & login → Where you're logged in, log out any device you don't know.
3. Turn on two-factor authentication and add a passkey.
4. Delete posts or messages you didn't send, and undo changes you didn't make.

If you still can't get in, contact CrowOn Support.