How do I fix my payment method. I'm getting the following Your service is on hold. Your service is on hold. Please contact us at xxx.xxx.xxxx.

Let me guide fix your payment method in QuickBooks Online, @peter81.

When you use QuickBooks Payments to process credit card and ACH payments, the payments go into the external bank account you pick. This is known as your payments account. 

Here's how to change your payment account: 

1. Sign in to QuickBooks Online in a web browser. 
2. Go to the Settings ⚙ menu and then choose Account and Settings.
3. Select the Payments tab.
4. In the Deposits section next to Standard Deposits, click Change bank.
5. Select Add new bank account.
6. Enter the Routing Number and Account Number of the bank account you want to change.
7. Select Save and then Submit once done reviewing the bank account info.

If you're referring to accepting payments in your invoices, I'm here to help set up your credit card payment method in QuickBooks Online: 

1. Go to the Gear icon, then select All LIsts.
2. Select the Payment Method, then click New.
3. Enter a name for the payment method. 
4. Once done, click Save.

Lastly, you can also update your billings and subscription if your account is on hold. 

Just in case, you can also check out this article for future reference: How to let my customer pay their invoice online.

Don't hesitate to drop a comment below if you have other questions about your payment methods in QuickBooks Online. Have a good day.