I activated my product key for Office 2021 and after I downloaded it, it says the product key is not activated.

Question

Hello, I was redirected to this forum from Microsoft community forum, the person who answered my inquiry told me to ask it here.

As the title says I activated the product key for Office 2021 Professional Plus, and I downloaded the Microsoft office. Afterwards I tried to work with the tools and it asked me to activate the product key again. I press the key to activate it and it says that it is already activated. Yes it was, by me few minutes ago.

This happened few weeks ago, during which I was able to use the Office, but now I cannot.

Today I went to setup.office.com to try and activate the key again. I did it and it gave me an option to download the Office, but it was link for 365 installation, which I didn't buy.

I tried to find any contact person from Microsoft but I cannot find any help. Side question, is there any way to communicate with customer support? I only get the options to communicate with the bots.

I saw the following post from this link, this person has the exact same problems as I do, and the people that answered don't seem to understand the problem (as well as 394 other people).

The product key was legally bought and it is valid, not at any point when I used the key did I get message it is invalid.

Thank you for your help in advance, I really appreciate it.