Thanks for getting in touch with the Community, Cath_R.

You can create automated payment reminders for invoices and include a message with them for your customers.

Here's how to turn on the feature:

1. In your top menu bar, go to Edit, then Preferences.
2. Access the Payments tab.
3. Open Company Preferences.
4. Choose Yes for your Do you want to send payment reminders? option.
5. Set a time and frequency.
6. Click OK.
7. Select Finish.

Now you'll be able to schedule payment reminders for invoices.
 

If there's any additional questions, I'm just a post away. Have a lovely day!