I have checked our record and haven't found a similar issue as yours. I suggest contacting QuickBooks Desktop Care Team, this way they can verify the issue and reach out to the engineers if needed. Here's how to contact them:
In your Quickbooks company, go to the Help menu, then select Quickbooks Desktop Help.
Click Contact Us, then enter your concern.
Choose how you wanted to be assisted.
Confirm your request.
Our Care Team is available weekdays 6 A.M. to 6 P.M. and Saturday 6 A.M. to 3 A.M.
Thanks for coming back here in the Community. I want to make sure you're able to connect the Bank of America (BOA) account in Quickbooks.
To ensure that I'm on the same page, are you using QuickBooks Online (QBO) Desktop App for Mac? If so, this has been reported as an ongoing issue with an investigation number INV-42974. Our Product Engineers are currently working to determine the issue and resolve it as well.
With this, I suggest contacting our Customer Care Team again. So they can add your company to the list of the affected users. Rest assured, we’ll update you about the status of the issue via email.
However, if you're using QuickBooks Desktop for Mac, I recommend creating a new test company file. This way, you can identify if the issue originates from your bank or your bank's servers.
Go to the File menu and choose New Company.
Type a name and hit Save.
Complete the required information in the Create New Company wizard and click Finish.
Add and set up online banking for BOA.
Choose Download transactions.
If there's no error message prompts, then the problem is not with your bank. To better resolve the issue, let's merge the accounts. This solution will help you determine if the issue is related to your account set up. For the complete instructions and other related topics, please browse through this article: Fix Online Banking. Directly go to Solution 2.