The most common reason for blocking the account is not paid in time conversations. In this case, to deal with the situation is very simple. Put money on the phone. Usually to unlock a simple rate should be at least 10 rubles. For the rate that is used to access the Internet, 50 rubles. When you put the money through the machine, consider the Commission.
The case may be, and is not in suspension of the account. Some of the rates when you reach certain figures of the balance sheet (positive), the ability to call is disabled.
Wait until the money comes to your account. Check your account balance. If you are "in the black" - let's move on. Try to make any operation using the connection. Send SMS, MMS, call someone. After that the account should unlock. Note that sometimes for full unlock you need to wait 24 hours.
If not, try to restart the phone. Again not out? Please contact customer support. Her number in MTS – 0890. In the voice menu until communication with the operator. Explain your situation. The operator will tell you what exactly is your problem and indicate the next steps. In particularly difficult cases you may need to go to the office of MTS. With this on hand, you must have a passport and a contract made when purchasing the SIMcard.
Money in the account is enough, but your number was suddenly blocked? Maybe it's the debt to another number. If your name was multiple SIM cards, you are responsible for the balance of each of them. And if the account is in one of the rooms go in the negative, will block rooms for you. In this case, you will have to repay all the debts.
The problem may not be the only expense, but also in the SIM card. Her lock occurs during a long non-use (60-180 days, depending on the tariff). In this case, the recovery SIM card is impossible. Also you can't go to the salon MTS and get a new SIM card with the same number.