How to Delete WhatsApp Account

To delete a phone number for WhatsApp Business Platform API, follow the below steps:

1. Visit the Facebook Business Manager, https://business.facebook.com/settings/

2. Then, select the business account, and go to your Business Settings page by clicking theSettings Icon button in the lower left corner.
3. Select, WhatsApp accounts → Settings → WhatsApp Manager

4. A new tab will open, there find the WhatsApp Platform you've created before, then click on it.

5. On the next screen, you'll see the phone number. Click on the Delete Icon button.