Hi there superfiddle,
It's vital that all your transactions are entered correctly for your bank balances to be accurate. QuickBooks Online is a great tool able to connect with different bank websites so you can import transactions. I can point you in the right direction for assistance with bank connection errors.
For help with bank connection errors, I recommend reaching out to the QuickBooks Online support team outside of the Community. They'll be able to do an analysis of the bank connection with you in a secure setting to be able to best assist you in getting those transactions, as well as collect the required information to notify our engineering team if the error persists after troubleshooting steps. You can reach them using these methods:
Schedule a Callback or start a Chat: click (?)Help in the upper right > type and enter "Contact support" into the QB Assistant > click Contact Us > explain your situation > click Let's Talk > choose Get a callback or Start a Chat.
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If you have any other questions, feel free to reach out here.