Before we dive in, could you share the name of your bank? It’ll help us craft a solution that fits you better.
QuickBooks only imports transactions once they are officially posted, so any pending payments won’t appear in the import.
Since you haven't seen any transactions, let's refresh the bank connection in QBO to restart the download process. Starting from the left menu, click All apps > Accounting > Bank transactions > Update.
Also, check your bank’s website for any alerts that might block QuickBooks Online from connecting. If transactions don’t appear after refreshing or reconnecting, you can upload them manually into QuickBooks Online.
If you have follow-up questions specific to the error message you're getting, leave a comment below.