I know it can be frustrating when you're unable to reconcile an account, LAM16.

Let me help you route to the right support available regarding your client's prior bank reconciliation concerns. You may consider contacting our QuickBooks Online Advanced Care Team. This way, they can check on this further by pulling out the account and do a screen-share with them to fix this. 

Here's how to contact them:

1. Go to this link: https://help.quickbooks.intuit.com/en_US/contact
2. Select your QuickBooks version.
3. Click Search for something else and enter bank reconciliation in the Tell us more about your question: box.
4. Click the Search button.
5. Choose a way to connect with us:
   >Start a chat with a support expert.
   >Get a callback from the next available expert.

Please let us know if you need anything else. We're always here to help.