Allow me to step in and help you further with resetting your check number in QuickBooks Desktop, stmnl7056.

Updating the QuickBooks Desktop release version is a good start when it comes to fixing data-related issues.

1. Click Help at the top menu bar and select Update QuickBooks Desktop.
2. Go to the Update Now tab. Tip: You can select the Reset Update checkbox to clear all previous update downloads.
3. Select Get Updates to start the download.
4. When the download finishes, restart QuickBooks.
5. Accept the option to install the new release.
   

After that, you can follow the steps below to verify and rebuild your data. This process examines the health of your QuickBooks company file. Here's how:

To Verify Data:

1. Choose Window at the top, then Close All.
2. Choose File.
3. Hit on Utilities.
4. Click Verify Data.

To Rebuild Data:

1. Choose File.
2. Click on Utilities.
3. Hit Rebuild Data.
4. You will receive a warning message to backup your company file, press OK.
5. Click OK when you get the message "Rebuild has completed".

Once done, you can follow the steps provided by my peer above to modify the check number. I recommend visiting this link: Account Management. These will provide links about managing your QuickBooks Online account, income, expenses, inventory, and running reports.

You can reach out to QuickBooks Community again if you need additional assistance. Simply click reply and I'll get back to you as soon as I can. Have a good one.