Let's run some steps to isolate the issue so you can continue managing your Bank of America entries.
To start with, let's refresh the connection between your bank and QuickBooks Online. To do so, you can follow these steps:
From the Banking tab, select Banking.
Click Update.
If the download appears stuck, we can sign in to your bank's website to check for any page maintenance notification. You can follow the steps outlined below to get your bank's URL.
Here's how:
On the Banking page, click Link accouunt.
Search for your bank and select it.
Copy the URL.
If you have more than 90 days worth of transactions to download, you can upload the rest of the transactions through a CSV file. Here's an article for the detailed steps: Manually upload the transactions.
I've also added a few links to help manage the your downloaded transactions: