A already paid invoice keeps coming back into my system as a new unpaid invoice. I have tried deleting the new one but Quickbooks continues to recreate a new one. Help ?

Welcome to the Community, @mkupgal.

I know this is new to your end, so let me share some insights and help you with your issue about the paid invoice marked as unpaid. 

I suggest accessing QuickBooks test drives in another browser. These will help us troubleshoot issues with the QuickBooks Online test account. Click this link to log in:

United States: https://qbo.intuit.com/redir/testdrive

United States QuickBooks Online Advanced: https://qbo.intuit.com/redir/testdrive_us_advanced

If that didn't work, it might be due to data corruption in your browser that can cause applications to crash or display data incorrectly. You can try signing in to your QBO using a private browser or "incognito" mode to fix this. This can help your computer or device run more efficiently.

 Here are the shortcut keys for these browsers:

• Google Chrome: press Ctrl + Shift + N
• Mozilla Firefox: press Ctrl + Shift + P
• Microsoft Edge: press Ctrl + Shift + N
• Safari: press Command + Shift + N

Alternatively, you can clear your cache; this allows you to refresh the website preferences, which may be causing issues when using QBO.

You can also check this article for more details about record invoice payments and how to upload your receipts to QuickBooks Online.

Please don't hesitate to reach out if you have any other questions or concerns. I'll be here to lend a hand.