Hi there, BobM.

Making sure you're able to do your daily task in QuickBooks Online is my priority. When QuickBooks or service isn't working, our Product Team will post an incident.
 

Upon checking from our QuickBooks Status page, there isn't a recent case about the issue. You can always visit the site to see if there’s an outage happening.

If you want to stay informed, select Subscribe to updates on the status page. We’ll send you a message when a service is down or scheduled for maintenance. We’ll also share the good news when it’s back up and running.

Going back to importing bank transactions, make sure to clear the history on your browser. To have the best and most secure experience with QuickBooks Online, use supported, up-to-date browsers.

Check out this article and find out what computer and browser you need when using QuickBooks: System requirements for QuickBooks.

Also, when importing bank transactions, you can upload CSVs with either the following 3-column or 4-column format. Please browse this article to see the sample table: Format CSV files in Excel to get bank transactions into QuickBooks. Keep in mind, the maximum file size is 350 KB. If the file is too big, shorten the date range and download transactions in smaller batches.

If you're having speed issues with your QuickBooks Online, there are several things that you can look at. You can browse this page to ensure you're getting the most out of your user experience: Why is my QuickBooks Online slow?

Please use the Reply button below if you have additional questions. I'll be right here to always assist you.