Joke Collection Website - Blessing messages - What does it mean for the calling user to open the SMS calling service?

What does it mean for the calling user to open the SMS calling service?

It means that the other party has started the SMS service.

The calling user has opened the SMS calling service, which means that the other party has opened the SMS calling service. When the other party's phone is turned off or there is no signal, you will call to remind the other party that the SMS calling service has been started, and he will receive the phone records you dialed when he turns it on.