Word code problems?

I re-instaled my laptop and bought a word 2019 code from a Saturn. When the laptop was restarted I was able to log in but I did not use Word, Excel, and PowerPoint anymore, they constantly ask me for a code, but I own it more. Can someone help with please I do not want to buy again a code for 100 euro.

Go to https://setup.office.com/ Then click on Install via your Microsoft account. Since you have already activated Word, the activation is permanently stored in your Microsoft account. Then entering the product key is no longer required.