If you become banned, you'll receive the following message from within WhatsApp:
"Your phone number is banned from using WhatsApp. Contact support for help."
Be aware that we ban accounts if we believe the account activity is in violation of our Terms of Service.
Please review the “Acceptable Use of Our Services” section of our Terms of Service carefully to learn more about the appropriate uses of WhatsApp and the activities that violate our Terms of Service.
We may not issue a warning before banning your account. If you think your account was banned by mistake, please email us and we'll look into your case.