App Store says computer is registered to a different Apple ID

Our company purchased a new 13" MacBook Air earlier this year for my coworker. Whenever we purchase a new Mac, I do the set up and configure it for the user... I install all the software and connect to our network, printers, etc. then give it to the user ready to go. To do this, I log in using my Apple ID and update all the software, then sign out of my account and remove that device from my list. This has always worked without any problem.

Now whenever the user tries to update or install anything on the App Store it says the computer is registered to another Apple ID. The device is not listed under my ID and it shows it is registered to the user. She uses this same Apple ID for email and on her iPhone and everything else works fine but for some reason the App Store on this Mac will not allow her access. I've tried signing back in with my Apple ID but I get the same error and it won't let me install any updates from the App Store either.

I tried to email Apple Support but it limits the description to 250 letters which is not enough to even describe the problem. Can someone point me in the right direction to resolve this?

Thank you.