Welcome to the Community, Darla.
A serial number won't change once an item is sold. There might be data damage.
Let's use the Rebuild Data tool that can resolve minor and common data issues. Here's how:
- Go to the File menu, then click Utilities.
- Select Rebuild Data.
- Click OK, then follow the onscreen steps to save a backup.
- Let the tool repair your file. It may take some time. QuickBooks may seem stuck, but as long as you can move your mouse, the tool is working.
- When the tool finishes, select OK.
- Go to the File menu. Then hover over Utilities and select Verify Data.
- Let the tool check your file for data issues.
If QuickBooks doesn't find any problems, select OK. If QuickBooks finds an issue with your company file, select Rebuild Now.
Here's an article to learn more about serial numbers in QuickBooks: Use Serial or Lot Numbers.
Please know that I'm only a few clicks away if you have any follow-up questions.
