Hacked phone

It is not true, you have been scammed. Delete the app, and restore your phone to a backup made before you installed it. If you provided any personal information act on the assumption that anything you provided, such as name, address, credit card, Apple ID, etc has been compromised.

If you provided your Apple ID and password change the password IMMEDIATELY! Change your Apple ID password - Apple Support

And see this for additional information→Avoid phishing emails, fake ‘virus‘ alerts, phony support calls, and other scams

Be very careful.

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

All such messages are scams presented by criminals. Never, never, never download anything based on a popup message. Delete the bogus app you have downloaded, and check that you have not been unwilling subscribed to the app.