I have read the whole thread regarding your bank feeds @lindsey21.
It seems that your bank account is already connected to QuickBooks. If you add the same account, you’ll get duplicate transactions.
To get this resolve right away, I recommend contacting our support team. They have the proper tools to identify the root cause of this issue.
You can also use this article on how to manually upload your bank transactions in QuickBooks Online: Manually upload transactions.
I'll be right here to help if you need further assistance. Keep safe.