https://support.facepunchstudios.com/hc/en-us/articles/214241045-EAC-Banned
EAC bans apply to the account even if it was hijacked at the time
The EAC ban cannot be removed regardless of who was using your account at the time it was banned. While we understand this can be frustrating we must have a zero tolerance policy for cheating to foster a fair game that players will enjoy. In order for a zero tolerance policy to be effective we must hold users responsible for the security of their account. When using Steam, please see the Account Security Recommendations FAQ to secure your account from attackers.

Thank you. As mentioned, I do not really care about the ban nor the game. I was just wondering what happened, if this has happened to anyone else and what to do in the future, since I did not recieve any requests as to a new log-in. It happened in different continents.

引用自 M.：

Thank you. As mentioned, I do not really care about the ban nor the game. I was just wondering what happened, if this has happened to anyone else and what to do in the future, since I did not recieve any requests as to a new log-in. It happened in different continents.

Also as a precaution, I would do these steps in order and in full to safeguard your device and account as the hijackers still may have access:-

Scan for malware https://www.malwarebytes.com/
Deauthorize all other devices https://psteamproxy.yuanyoumao.com/twofactor/manage
Change passwords once your device is 100% clean
Generate new backup codes https://psteamproxy.yuanyoumao.com/twofactor/manage
Revoke the API key https://psteamcommunity.yuanyoumao.com/dev/apikey

Thank you. Will do. Really appreciate the help.