Niantic now sending ban emails.

Trainer,

Your account has been terminated. Use of any other third-party software or app, including but not limited to scripts/apps, applications used to falsify your location, emulators, modified or unofficial software, and/or accessing Pokémon GO clients or backends in an unauthorized manner is considered cheating.

If you believe your account has been terminated in error, you may fill out this form. Please consider your account permanently terminated unless we reply back to your appeal.

- NianticOps


For those of you wondering if it's an error or you're banned. Check registered emails.