Thanks for checking out the Community space, anna-buildseattl.

In addition to jvanlanduyt's explanation, this error normally occurs when QuickBooks is unable to establish a connection to your bank. To isolate the issue, you can refresh the connection by running a manual update. I'll guide you how:

1. Select Transactions or Banking from the sidebar menu.
2. Go to the Banking tab, then choose the appropriate bank account.
3. Click the Update button.
4. Enter your Multi-Factor Authentication (MFA) credentials if prompted, then hit Continue Update.

If the same thing happens, you can update your banking information. Feel free to follow the steps below:

1. Select Transactions or Banking from the sidebar menu.
2. Go to the Banking tab, then choose the appropriate bank account.
3. Click the pencil icon, then select Edit sign-in info.
4. Enter your online banking credentials, then click Update.

I've also included some articles that will help you categorize your bank transactions and fix common banking errors in QuickBooks Online:

•  What to do if you get a bank error or can't download transactions
• Categorize and match online bank transactions

Keep me posted if you have any other concerns or follow-up questions. I'm always here to back you up.