I cannot use it with other simcard

i think your phones is programmed for suppoting one kind of sim card chech if your handset is cdma or gsm if its is cdma it will not suport gsm sim cards but it will support all kinds of cdma sim cards and if it is gsm it will support only gsm sim card not cdma if its is progrmmable phone take to service center and check whether the phone have the capability to support both gsm and cdma