After I check with call center,
They said fist try to change sim card to another phone if can not use it’s mean sim card have problem
But if can use with another phone it’s mean yr. phone have problem.
Can change new sim card and check yr. mobile at AIS shop Teminal 21, 5 floor.
If you not convenient, Pls. send to me.
Sorry for late reply, Because I await AIS check and reply.