Recently, automatic messages are being sent to my vendors indicating that an invoice is overdue. Why did this start? Can it be stopped, please?

Yes, that can be stopped, @btmoore.

The automatic due message sent to your vendors starts if the Automate invoice reminder is turned on. 

Let's go to the settings of your account to turn off the feature. So moving forward, there's no electronic message sent.

Here's how: 

1. Click the Gear icon at the top right, then choose Account and settings. 
2. Select the Sales tab. 
3. Hit the Edit button perpendicular to Reminders. 
4. Turn of Auto invoice reminder. 
5. Tap Save, then Done. 

For more details about the process, check out this article: Automate invoice reminders in QuickBooks Online.

Instead of automatic, you can also send them manually by going to the Invoice page, then hit the drop-down arrow under Action, and tap Send Reminder. 
 

You can always access invoice reports by going to the Reports tab on the left. Then customize it to show the specific details.

Additionally, I've added articles about how to create templates for recurring transactions and personalizing sales forms in QuickBooks Online. 

• Create recurring transactions
• Customize invoices, estimates, and sales receipts

Please leave a comment below if you have other queries. I'm delighted to assist. Take care always.