Welcome to QuickBooks Community, steve204.
There are two fields when composing your question before you post it here. You can add details of your concern in the Details section.
Also, are you referring to the account on your Banking/Transaction tab? If so, we can manually update it to bring in the transactions. Simply go to the Banking tab and select Update.
In addition, you'll want to check your bank or credit card's website to see if there's an issue on their end. This will block the connection between the bank and QuickBooks Online which will result in the transactions won't download.
I've added these links for more details about banking:
Post again anytime if you need more help. We'll respond as soon as we can.