Why cannot delete a check that has not been cleared the bank

I got you covered, @mercedes_harper-.

I can provide you with some details about uncleared checks in QuickBooks Online (QBO).

In QBO, we can leave the uncleared checks alone as they haven't yet been settled with your bank. The reconciliation page can be filtered to only display cleared transactions.

Since you want to delete the uncleared check, please follow the steps below:

1. Go to the Accounting menu then Chart of Accounts.
2. Locate the account where the check is posted.
3. Under the Action column, click on View register.
4. Click on the Filter dropdown above the Date.
5. Select Not Reconciled under the Reconcile Status.
6. Select Check under the Transaction Type dropdown list.
7. You can also filter the Payee and Date dropdown lists.
   
   
    
8. When done, click on Apply.
9. Click on the transaction then hit Delete.
   
   

Upon doing this, I still advice speaking with an accountant before making any alterations to your account. It's possible that he or she has precise guidelines on how to manage these transactions. 

In case you need help in doing or fixing a reconciliation in the future, feel free to browse through this article: Start, fix, and edit a complete reconciliation in QuickBooks Online.

Should you have additional questions about bank transactions QBO, please don't hesitate to reply to this post. I'll be willing to lend a hand. Keep safe.