Need to void a [payment a client made in error...and quickbooks offers zero ways to connect with someone

Have you tried clicking on the help button at the top right of QBO and then selecting "contact us?" You can chat with support using this feature if you don't find what you're looking for.

I can help you void a customer payment, tony-jones.

You can follow the easy steps on how to void a payment in QuickBooks Online so everything is processed and your books stay accurate. 

1. Click the Sales menu and select Customers.
2. Locate for the customer's name and go to their Transactions list.
3. Look for the invoice you want to void the payment for and click the drop-down arrow under the ACTION column.
4. Select Void.
5. Click Yes. 

If you want to get in touch with our Phone Support Team, you can go to the Help menu at the upper-right as @stciuk122 suggested. You can also click here for more information about our support hours and types. 

I'll be attaching a few articles below that will help you manage customer payments: 

• Void or refund customer payments in QuickBooks Online
• Record and make bank deposits in QuickBooks Online

Keep me posted if there's anything else that you need help with. I'll be more glad to assist you. Have a good one!