In case you can no longer delete or void the check, I suggest reaching out to our Customer Support team. They can get into your account in a secure environment and edit or process the correction.
Follow the steps below:
Go to the Help icon to connect to a live support agent.
Click on the Contact Us button and provide some details about this concern.
Provide us some information about your concern in the What can we help you with? box and click on Continue.
You'll now be provided options on how to connect to our Customer Support.
You can check this article for more information about the different types of support we offer and their availability: QuickBooks Online Support.
If I can be of help while working with your payroll checks, let me know in the Reply section below. I'll be here to help. Have a good one!