Does buying cheap software online violate copyright?

I need to buy a Microsoft Office account to work. When searching online, I saw many places selling accounts for a few hundred thousand dong, while the price in other places was much higher.

The seller provided me with an email address and password, claiming this is "genuine, with warranty". I would like to ask if I buy it and use it, is it considered using copyrighted software? Is there any violation?

Reader Hoang Nam

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