My bank transactions doesn’t always find matches in expenses and there are matches there when you go into ‘match’. It always used to show matches

I'm pleased to have you in the Community, @ktsnld. I'll share some details on why you're unable to match transactions in QuickBooks Online (QBO). 

There could be various reasons why certain transactions do not appear when you click the Find Match option in QBO. Please see below:

• The transactions entered in QBO don't simply match the number, amount, date, or payee of your downloaded bank deposits.
• The transaction/s you want to match have been reconciled.
• The transaction entered in QBO has already been matched to another downloaded transaction.
• The transactions were downloaded twice. If these transactions have already been added to QBO and have a lightning bolt in the CLR column, they will not be matched again.

Once we have verified all the details, we can make use of the Find Match function to display all the transactions that could potentially match. To accomplish this, follow the instructions provided below:

1. Go to Banking and select the Banking tab.
2. Click the Find other records button.
3. In the Match Transactions window, put a checkmark on the transactions that should match the downloaded transaction.
4. If the transaction you want to match is outside the date range displayed, update it. You can click the date field to manually change the From and To dates.
5. Select Save if the total amount of both transactions is the same.
6. Click Save.

You can refer to this article for the complete guide on how to add and match downloaded transactions in QBO: Categorise and match bank transactions in QuickBooks Online.

In case you would like to reconcile your account, here are a few additional articles to help you accomplish a successful reconciliation: Reconcile an account in QuickBooks Online.

If you have any further questions or concerns related to the current topic, please feel free to reply to this thread. I am here to assist you to the best of my abilities and provide you with the necessary information.