If you are seeing the message "You're temporarily banned from WhatsApp," it means that you have violated WhatsApp's terms of service. WhatsApp bans users for various reasons, including sending too many messages to people who do not have your phone number saved in their contacts, using third-party WhatsApp clients, or engaging in inappropriate behavior.
If you have been banned, you will have to wait for the ban to expire before you can use WhatsApp again. WhatsApp typically bans users for a limited time, ranging from a few hours to a few days. However, if you continue to violate WhatsApp's terms of service, you may be permanently banned from using the app. To avoid getting banned from WhatsApp, make sure you are using the app in accordance with its terms of service and community guidelines.
Cheers,
WhatsApp Support Team