The account has a GAME ban

https://steamhost.cn/steamcommunity_com/discussions/forum/9/620712364027233611/

Game bans have nothing to do with VAC or this forum

Users are responsible for the security of the account and all that happens on it

Buying or selling Steam accounts is a violation of the Steam Subscriber agreement and could end with ANY and ALL associated accounts deactivated.

You've a game ban. This may be for variety of reasons - including cheating, griefing etc.
CS2 game ban
https://steamhost.cn/help_steampowered_com/en/faqs/view/4E54-0B96-D0A4-1557
Other games
https://steamhost.cn/help_steampowered_com/en/faqs/view/46DB-4CEC-F7E9-49E5