The next day i realized that it was office online. I lost my original windows with pre installed office 2019. However, my windows is activated. Dell gave me office Home Student 2019 offline installer. After install the office i checked via command prompt, and it showed me like this. C:\Program Files (x86)\Microsoft Office\Office16>cscript ospp
There are no work-arounds for the above. #2 - Even after activation, Office needs to connect to the activation servers once every 30 days to remain active. #3 - Once a product key is associated with a Microsoft Account, it is permanently digitally associated with that account and is no longer required. The "product key" you see on the site is UXBQAm.