This happens when you have used multiple login methods (i.e. you logged in with Facebook, then separately logged in with an email address).
We suggest using the same login method to keep your points and progress saved.
If you accidentally created a new account, delete the app, install it again and login via correct login method.
If you don't remember your correct login method, please send us a screenshot of your profile page and how your other username(s) appears in the app and we will fix it.