It seems that you're uploading receipts on the QuickBooks Online mobile app. Allow me to help you.
You'll be able to categorise the receipt once it's uploaded through the app. From the Menu, select Receipt snap, then go to the For Review section. From there, you'll see all pending receipts and you'll be able to select an account and enter a description.
Visit the App Store or Play Store to make sure that the app is updated. We can also clear and resync your data to fix unusual behavior by following these steps:
Click the Gear icon.
Find and select Refresh Data.
Tap Yes to confirm.
If the same thing happens, it's best to uninstall and reinstall it.
I added these links for your reference on how to manage your receipts and connect your bank to automatically download transactions: