Steam account banned

Hello, my name is Dmitry and on January 30 I was blocked. Who can help please write!
"This account is associated with stealing the accounts of other Steam users. This account has been flagged by Steam

Support for stealing the accounts of other Steam users and, as such, for violating the terms of the service agreement. Purchases, gifts, trades, activation of digital keys and access to the Steam Community are now disabled.


Account capabilities have been restricted.

If you believe you received this message in error, please contact Steam Support so that we can assist you.

Please refer to the Steam Service Agreement for more information on this topic."

I did not commit any activity with the theft of accounts, the account was blocked without reason. Exchanges made only with friends. Posted on STEAM I support the answer below

We have found activity in this Steam account related to the hijacking of another user's Steam account.

Per the Steam Subscriber Agreement, we have locked the account. The account will not be unlocked.

The Steam Subscriber Agreement can be found at:
http://store.steampowered.com/subscriber_agreement/

In addition to violation of contract, activities on the account may violate federal law and state law. If such activities persist, Valve reserves the right to refer the matter to authorities.