A computer-implemented method for availing at least one service by a user equipment while in an international roaming, the method comprising: - transmitting, by the user equipment having a home International Mobile Subscriber Identity 'IMSI', an attach request to at least one second network when the user equipment is in the international roaming by entering a second location from a first location, wherein the first location is served by at least one first network and the second location is served by the at least one second network, and the home IMSI corresponds to the first location; - receiving, by the user equipment, an attach reject in response to the attach request, wherein the attach reject is received from the at least one second network and the attach reject comprises a reject cause other than Public Land Mobile Network 'PLMN' not allowed; - updating, by the user equipment, at least one location parameter of the second location at the subscriber identity module, wherein the subscriber identity module is configured at the user equipment, and the at least one location parameter has an associated status; - analysing, by the subscriber identity module, the associated status of the at least one location parameter of the second location; - requesting, by the subscriber identity module, to receive at least one network parameter of the at least one second network from the user equipment when the associated status of the at least one location parameter corresponds to the attach reject; - communicating, by the user equipment, the at least one network parameter of the at least one second network to the subscriber identity module, wherein the at least one network parameter comprises a mobile country code of the second location; - replacing the home IMSI of the user equipment with a global IMSI, by the subscriber identity module, when the at least one network parameter corresponds to the second location; - re-transmitting, by the user equipment having the global IMSI, the attach request to the at least one second network; and - availing, by the user equipment, the at least one service while in the international roaming when the at least one second network accepts the attach request with the global IMSI. - transmitting, by the user equipment having a home International Mobile Subscriber Identity 'IMSI', an attach request to at least one second network when the user equipment is in the international roaming by entering a second location from a first location, wherein the first location is served by at least one first network and the second location is served by the at least one second network, and the home IMSI corresponds to the first location; the first location is served by at least one first network and the second location is served by the at least one second network, and the home IMSI corresponds to the first location; - receiving, by the user equipment, an attach reject in response to the attach request, wherein the attach reject is received from the at least one second network and the attach reject comprises a reject cause other than Public Land Mobile Network 'PLMN' not allowed; - updating, by the user equipment, at least one location parameter of the second location at the subscriber identity module, wherein the subscriber identity module is configured at the user equipment, and the at least one location parameter has an associated status; the subscriber identity module is configured at the user equipment, and the at least one location parameter has an associated status; - analysing, by the subscriber identity module, the associated status of the at least one location parameter of the second location; - requesting, by the subscriber identity module, to receive at least one network parameter of the at least one second network from the user equipment when the associated status of the at least one location parameter corresponds to the attach reject; - communicating, by the user equipment, the at least one network parameter of the at least one second network to the subscriber identity module, wherein the at least one network parameter comprises a mobile country code of the second location; - replacing the home IMSI of the user equipment with a global IMSI, by the subscriber identity module, when the at least one network parameter corresponds to the second location; - re-transmitting, by the user equipment having the global IMSI, the attach request to the at least one second network; and - availing, by the user equipment, the at least one service while in the international roaming when the at least one second network accepts the attach request with the global IMSI.