Steam Support is unable to remove your VAC ban. We have a zero tolerance policy on cheating. Even if the ban was the result of a hijacked or shared account. You are responsible for the security of your account.
Steam Support will not provide you any details on the cause of the ban or the date and time of the infraction. Your in-game items will be locked and cannot be moved from your inventory.
If you'd like to play the game again on VAC secured servers please make sure you repurchase the game on an account which has not been VAC banned.