For the app "Cloudless" (app.cloudless) on Google Play
This permanently deletes your cloud backup, your sync account (including your email, if you added one), and the data stored on the phone. There is no recovery.
If you only want to wipe your data but weren't using a sync account, the Reset everything row on the same tab erases the phone data and any anonymous backup.
Lost the phone or uninstalled? Email support@getcloudless.app from the email address you used for sync, with the subject "Delete my Cloudless account". We verify it's you and delete the account and backup within 30 days (usually much faster), then confirm by reply.
Google Play keeps its own purchase records under your Google account; manage those in Google Play. Subscriptions must be cancelled in Play subscription settings — deleting the account does not cancel a subscription.