Hi there, @Michael7s.

I'm here to help ensure your PayPal transactions are not duplicating your sales. 

To fix this, we need to match them with your sales receipts. Here's how: 

1. Go to the Banking page. 
2. From the Bank and Credit Cards drop-down menu, select your bank account.
3. Under the For Review tab, find and click your PayPal payment transaction, then select Find Match.
4. Choose the sales receipt.
5. Click Save.

Here's an article for an additional guide on categorizing or finding a match of your downloaded banking transactions.

For future reference, read through this article to learn about balancing your checkbook to match your QuickBooks transactions with your PayPal, bank, and credit card statements: Reconcile an account in QuickBooks Online. 

Visit us again here in the Community and post some more if you have additional concerns. I'm here to keep helping. Take care!