You can check your username by opening the Covve app, tap on the gear icon (top right) -> Account -> Account Info

If you signed up to Covve using the email and password option, your Covve username is the email you provided during the sign-up process.

If you signed up with Google, your username will be the e-mail associated with your Google account. 

If you signed up with Apple, your username will either be the email associated with your Apple account, or, if you chose to hide your email from Covve, it will be an anonymous email provided by Apple.