First, tap on your own profile picture or username on any menu within PlayLah that shows it, to bring out your detailed profile panel.

From your detailed profile panel, tap on Settings > Permanently Delete Account.

A pop-out menu will appear, prompting you to confirm your request to delete the account.

Please note that tapping on "Confirm Deletion" will begin the account deletion process. Once completed, all your game progress, along with any purchased or earned virtual goods and currency, will be permanently deleted and cannot be recovered.