bank account unlinking

I appreciate you for posting here, Dean.

I see how challenging it is on your end to perform your daily banking tasks because of the sudden disconnection between your bank and QuickBooks Online (QBO). Let me direct you to the best help for this.
 
Since it has been a recurring issue on your end for over a year, I recommend contacting the QBO Care Team to further isolate this issue and find a fix. Here's how:

1. In your QBO account, click the (?) Help icon.
2. Tap the Search icon, then Contact Us.
3. Enter a brief description of your concern and Continue.
4. Choose if you want to Start a chat or Call us.

Take note that chat support is available all day from Monday to Friday. However, if you want a live call, we're available Monday to Friday, 8:00 AM to 10:00 PM, and Sunday to Saturday, 8:00 AM to 6:00 PM.

Also, I'll share this article to help you solve some basic banking error that shows on your end: Fix bank errors in QuickBooks Online.

Moreover, if you want to categorise your downloaded bank transactions automatically, check out this article: Set up bank rules to categorise online banking transactions in QuickBooks Online.

Let me know if you have additional banking-related concerns in QBO by replying to this post. We'll reply as soon as possible. Thank you, and have a good day.