Mobile phones utilize a card called a SIM card. This stands for Customer Information Module, and each one consists of a special serial number. The SIM card recognizes the person who is using the phone. The cellphone business lock the phones so that a SIM card from another business can not be used. When your phone is leased from the company, this locking is great, as you are supposed to utilize the phone's network anyhow, but when you are the owner of the phone, it may be a issue.

imei repair service