If you used a mobile-pocket account with an e-mail address tap on "burger icon" in the top left corner and then on "Account" -"mobile-pocket Account". Click on "forgot password" and enter the e-mail address, with which you registered. You will automatically receive a password sent to this e-mail addresse, please also check your spam folder.
If you can't see this section, it means you're already logged into an account.
 
If you registered with your Facebook, Google or Apple account please request a new password directly from the respective platform.