My banking transactions are not showing up after updating and also reconnecting the account.

Welcome you to our Community, Gwen.

To assist you better, we kindly request you to provide us with some additional details regarding your bank feeds. Could you please let us know which bank you are trying to connect to QuickBooks Online (QBO), and what is the date range of the transactions you are attempting to upload?

Please note that you can check your bank's website to see if the transactions have already been posted. In case they have been posted, kindly check for ongoing maintenance, as this may be the reason why transactions aren't appearing in your QBO.

Moreover, you may refer to this article if you encounter specific problems while uploading your bank feeds: What to do if you get a bank error or can't download transactions in QuickBooks Online.

Once you have successfully uploaded your transactions, you can proceed to reconcile them to match your bank feeds to QBO. 

If you have any further questions regarding your bank transactions, please feel free to comment on this thread. The Community Team will be here to provide you with the help you need.