If it has no service then maybe you are using an incompatible phone..Did you buy the phone internationally ?..Many International phones like Xiaomi, Etc dont have the American Bands . Try with a different phone.
When you activate it gives you the option to choose a new number or transfer a number . Choose transfer a number and keep your previous providers account number handy ...Once you put in the details and submit ...it will transfer over within 2 hours
