How to change my phone number on Whatsapp?

[astroXP]

I recently got a new phone and since I might not request to transfer my old number (and to avoid this again in the future), I'm trying to change my phone number to my Google Voice number on Whatsapp.

According to their FAQ:

I changed my phone number, how can I update WhatsApp?

Step 1: update your WhatsApp status with new phone number. Step 2: delete WhatsApp and re-install and register with your new phone number

I already did this several times but instead of recognizing or linking my old account with this number, it is actually creating a new account. The problem I have with this is that I'd lose my paid account (set to expire on 2021) and the new account expires in a one year.

Do I have to input my phone number in international format? How long should I wait until I install the app on the new phone and set up my account? If this keep failing, what should I do? (I already contacted Whatsapp, and boy, what a bad customer service, they haven't replied in a week)

[metro2012]

The problem I have with this is that I'd lose my paid account (set to expire on 2021) and the new account expires in a one year.

the free account never expires. It auto renews itself. If its a glitch on WhatsApp's part, shhhh, but it happens on all Android ive seen.