A SIM card, or Subscriber Identity Module, is a small card that stores information about a subscriber to a mobile network. This information includes the subscriber’s phone number, account details, and other data. SIM cards are used to identify subscribers to the network and to allow them to access services such as voice calls, text messages, and data services.
In some cases, a SIM card may become locked. This can happen if the SIM card is inserted into a phone that is not authorized to use it, or if the SIM card is lost or stolen. A locked SIM card cannot be used to access any services on the network.
