the best likely course is to contact customer-support and
ask for examples of what may be triggering the policy-flag --
https://support.google.com/google-ads/contact/approvals

 

also, verify that no other ad-account has ever been opened --
only one google-ads term-of-service has ever been accepted.

 

verify a valid payment-method is under their linked google-account.

 

verify that any and all payments to google have
all been paid in full -- not only google-ads:
https://myaccount.google.com/payments-and-subscriptions
https://myaccount.google.com/subscriptions
https://myaccount.google.com/purchases

 

verify the payment-method is allowed in the
specific country associated with the business --
https://support.google.com/google-ads/answer/2375432
https://payments.google.com/payments/paymentsinfofinder

 

otherwise, consider changing the payment-method to conform to the policies:
https://support.google.com/paymentscenter/topic/9017383

 

only then, consider contacting google for a formal appeal:
https://support.google.com/google-ads/answer/7217078

 

otherwise, most such suspensions are permanent and cannot be fixed.

 

please note that accounts related to a suspended account --
such as accounts using the same email or payment method,
or accounts linked to the same manager-account are also
at risk of being suspended.

 

unfortunately, most suspicious-payment-activity policy-flags
result in a permanent suspension from the program -- unless
the policy-teams find a mistake in the original policy-flag.
 
such a permanent suspension is against the advertiser --
not any one particular account, nor any one particular
website or channel, nor any particular payment-method.

 

if the policy-teams have placed a permanent-suspension against the
advertiser, then no further advertising with google is ever allowed --
any new accounts created will simply be suspended again, eventually.

 

that being said, google is the final arbiter.