Below is the template we use for our Return Received Email - which your customer receives when you mark their return items as received.
You can modify both the Heading "We Received your return for Order" and the body in the settings.
To do so, go to the app settings, select the Returns Dashboard tab, and you will find the relevant card in the "Notifications" section.
Note: the "Exchange It Testing" at the bottom is just our testing store's name. Your store name will be displayed there.