Lost microsoft office license after resetting windows

I had a similar concern with a pre-installed Office license, and the important thing seems to be determining whether the license was Microsoft-account based or device based. Dell’s current guidance says that most licenses are Microsoft-account based, while some devices use a device-based license. Since your Office was active before the Windows reinstall but isn’t showing under your Microsoft account now, I would contact Dell support first and ask them to verify the Office license that was originally shipped with your Dell Pro Micro. They may be able to confirm the license type and explain how it can be recovered. I’d definitely avoid purchasing another Office license until they check the original entitlement.

If I want to ask Dell, what can I do? Can you explain the steps? And will it affect the warranty process?

Please can you confirm the Make Model and OS, along with any configuration details like touch screen, backlit keyboard, SFF or tower etc etc.

@duwisetiawan​

Contact Dell GHN (Get Help Now) chat technical support Monday through Friday. Click the blue "Get Help Now" on the right to start a private live chat session. Share the private Service Tag with them so that they can verify the ownership and warranty status. This will also generate a unique Technical Support case for your unique Service Tag. 

Office Activation Keys should be tied to the Microsoft Account that was used upon the first sign in with an Office app. If the key is not present in your MSA but was previously activated, then this typically would be seen as a Microsoft issue. It sounds like you are using the correct email as well where the key should have been stored. See this article for additional activation details. 

@DELL-Daniel V​ If the problem is with Microsoft, do I need to open a ticket with Microsoft or do Dell help handle it?

@duwisetiawan​ You would want to contact Microsoft directly. The article I shared has the steps on how to get in contact with them. The only info you may need from Dell is your order number when you purchased the system. Microsoft typically uses that to validate that Office was purchased with the unit.