Incomprehensible ban the account. Please administration help. (Diablo 2)

This morning I went before work to do a few runs on Andy on account of pup-c, everything was fine. After work, when you try to log on the account, writes that the access account is closed. Please administration help and explain what is the reason for the ban, because in this account I invested all of his strength, and it is a shame if I lost him.