There are several options to reset your two-step verification PIN.

Reset PIN with an email address
If you provided an email address when you set up two-step verification, you can reset the PIN immediately by requesting a reset link.

To reset the PIN:
Open WhatsApp > tap Forgot PIN? > Send Email. A reset link will be sent to the email address you provided.
In the email, follow the reset link and tap CONFIRM.
Open WhatsApp > tap Forgot PIN? > Reset.
Keep in mind, deleting or reinstalling WhatsApp won't disable or reset the PIN for two-step verification.

Reset PIN without an email address
You’ll need to wait 7 days to reset the PIN if:
You didn't provide an email address to reset the PIN.
You forgot the email address to reset the PIN.
Someone else set up the two-step verification PIN before you started using this phone number.
After the 7-day period, open WhatsApp > tap Forgot PIN? > Reset.

Note: For security purposes, there isn’t an option for us to speed up the 7-day timeframe or disable your account after two-step verification is enabled. The two-step verification PIN is different from the 6-digit registration code you receive via SMS or phone call.