Reminders on overdue invoice to customer

Hello, Chipndale. 

Thank you for reaching out to the Community. In QuickBooks, sending a reminder to an overdue invoice is included in the default email body message. Let's isolate this case by performing a troubleshooting step to determine it's related to a browser issue. There are times that the browser stores frequently-accessed data, thus causing some errors or unusual behavior. 

We can start by accessing your account in a private browser. This mode doesn't save your searches, visited pages, log in details, and cookies. Like Google Chrome: press Ctrl + Shift + N, Mozilla Firefox: press Ctrl + Shift + P, Safari: press Command + Shift + N and Microsoft Edge: press Ctrl + Shift + P.   

If you're able to view the default message upon sending to an overdue transaction. You'll need to clear the cache of the regular browser you're using. Clearing the cache or cookies is the best way to get a clean slate for your browser. Or you can use other compatible browsers. It could be that the one you're currently working on has a temporary issue with QuickBooks.   

You might want to check out recurring invoices. It helps manage your time and performing a series of transactions according to the schedule you set.  

If you have any other questions, just let me know. I'm always happy to assist you further. Have a great day ahead, and stay safe!