I want to buy office 2021 pro plus. But my financial condition isn't so good and right now I can't afford the price Microsoft official store are offering. So I try to search for cheap office 2021 pro plus. Then I found the website called MSCDKEYS. Then I visit it and explore that. It seems legit and also they have Microsoft's official partner id. So here I'm confused. Is it really legit? Can I buy from them? Thank You.

I wonder why no answers to this? I'd be interested too. In the absence of an answer, I'd look for reviews from that company.

I just bought MS Office 2021 Pro Plus for $20 at Digitlogs.

In which case you probably bought a pirated copy. When MS learns about the pirated keys being used to activate the product, they'll simply invalidate those keys. Your Office installation will soon stop working.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]