I would like to change the template email for payments.

Hi ros-hazen-khs,

Being able to edit the emails you send to your customers is one of the ways you can add your own personal touch to your QuickBooks Online Account. QuickBooks Online makes editing your email template as easy as 1,2,3 and I'd be happy to help go over how.

There are many kinds of email templates in QuickBooks Online and good news, they are all in the same place. To edit your template you can follow these steps: Gear>Account and Settings>Sales>Messages. Once you click on messages you can select the type of email from the drop down under sales form. Once the type of email is selected you can edit the greeting, subject line, message and a few other options. 

In case this doesn't fix the issue you are having I suggest getting in touch with our support team to provide a more one on one troubleshooting experience. You can contact them by following the steps in this link.

Hope you have a great one!