I've been trying to add a payment method to my Amazon Seller Central account but have been unable to do so because I never receive the security code on my phone. Amazon support couldn’t determine the cause of the issue either. I have already contacted AT&T, and they confirmed that there is no blockage on their end. Interestingly, I always receive security codes from Amazon when logging into my account. The issue seems to be specific to Amazon Seller Central when attempting to add a payment method.
Any way I can bypass that security notification so I can add my payment method?
Since you receive the OTP for login but NOT for changing the payment method that means that you are not the "Primary account manager" but that you have a user permission.
Only the person who CREATED the account and is the owner of the "Primary account manager" email and phone number can modify the payment method.