How do remove recorded payment from an invoice? I accidentally selected the wrong payment and I cannot unlink it from the invoice.

Hey there. 

We can remove the recorded payment from an invoice by deleting it. This way, you can record the payment again to the correct invoice. Here's how:
 

1. Go to Sales and select All sales.
2. Look for the payment, then click the Action drop-down list.
3. Choose Delete.
4. Select Delete again to confirm.

Once done, you can now recreate the invoice payment and apply the correct payments to your invoices. You can use this resource as your reference: How to Receive and Record Invoice Payments in QuickBooks Online.

Moreover, you can run sales reports in QBO to get helpful insights about the things you buy and sell, and the status of your inventory.

If you have additional questions about removing incorrect payments in QuickBooks, just post them again in the thread. We'll be here to help you out.