I have had to delete a lot of incorrect and duplicate transactions. However, when the account updates, it puts everything that I deleted back and I have to start over.

I can share with you a way on how to not start over the incorrect downloaded transactions in QuickBooks Online, sandrea.
 

We can exclude unnecessary transactions instead of deleting them out. I would recommend excluding the duplicate or incorrect ones to keep them out from the other usable transactions. I'll provide you the steps on how to do it:

1. Go to Banking and select the Banking tab one more time.
2. In the For Review tab, tick the duplicate and incorrect transactions next to the Dates column.
3. Click the Batch actions drop-down arrow and select Exclude Selected.

Along with these steps, here's a screenshot for additional reference:

I'm adding two articles below that will help you about doing things in the Banking page:

• Matching and categorizing bank transactions.
• Assigning, editing, and adding your downloaded banking transactions.

I'd like to have you back and help you out with your QuickBooks concerns more. Please add a comment below if you need further assistance! Thanks! Take care!