How do I change the customer name on a payment without clearing the payment amount? Every time I try to change the customer name the payment amount changes to zero.

Hello, jondalrymple.

I'd like to give an idea to help you process a customer payment.

Changing the customer name will also change how credits and payments were applied. You can delete and reprocess the payment in order to select the correct customer name. 

Here's how:

1. Go to Sales on menu ☰.
2. Click the Customer tab.
3. Select the name of the customer on the original payment.
4. Locate and open the transaction.
5. Click on More, then select Delete.

Once done, you can redo the payment with the correct customer name.

Like this:

1. Click on +New
2. Select Receive payment.
3. Select the customer name on the drop-down.
   Note: It will automatically choose any open invoice for the customer you selected.
4. Enter the amount.
5. Click on Save and Close.

I'll be adding this link for more information about payment: Take and process payments in QuickBooks Online

Let me know if you have further questions or concerns, I'm here to help. Have a nice weekend!