Telecom cards bought in the United States can receive calls and messages online, but can't send messages by phone. Why? How to solve it?

First, check whether the SIM card is damaged or installed incorrectly. If not, please follow these steps:

Set the phone to flight mode first,

Then open the closed cellular data network.

Then turn off the flight mode of the phone.

You can make a phone call when the signal comes out.

Don't worry ~ ~ be patient

Mine is the same problem, which has been solved.

If this method can't solve the problem after repeated several times, it is suggested to overcome the detection.