Overview
If you want to switch from using the regular WhatsApp app to the WhatsApp Business API, it's a straightforward process. You can actually use the same phone number that you have saved in the WhatsApp app on Android, iPhone, or the Business application.
However, before registering that phone number for the WhatsApp Business API, you need to remove the WhatsApp account associated with it. Just follow these instructions to do it.
Note:
Keep in mind that any messages you receive during this process will be stored by WhatsApp servers and delivered once the registration is complete.
Step 1. Disconnect your number from the Whatsapp app
Launch the WhatsApp (or WhatsApp Business) app on your iPhone or Android.
Go to the Settings page.
Select your Account.
Select Delete my account.
Note:
The disconnected number may take up to three hours to reactivate.