An invoice was paid and shows in online banking though the payment doesn’t show at all in QB banking - 4 weeks ago. Other payments were made the same day which do show

I can show you how you can bring your transactions into QuickBooks, dean28.

You can further check the bank downloaded transactions first by using the Filter option. Select the date range when the transaction was missing.

The system downloads the most available transactions. If the auto-download got stock, we can do a manual update. 

1. Go to the Banking menu or Transactions menu.
2. Select Banking tab.
3. Click Update.

The number of transactions in the bank account tile will increase if QuickBooks downloads new transactions. Then, filter the For review tab again.

If it still didn't download, the issue may be on the bank’s end. You can log in to the bank's website to look for any alerts or maintenance they have. While waiting for it to be fixed if there's one, you can manually upload missing transactions. 

Keep me posted if you need more help in handling your bank transactions. Take care and stay safe!