Apple phones can send text messages but not make phone calls.

1. At present, there are two reasons for the poor network signal, namely, the operator's problem and the user's own settings. However, due to the SIM card, it is temporarily unable to pass its own replacement test.

Second, if it is due to its own settings, it is recommended to restore the network settings.

Thirdly, if it is the operator's problem, it is suggested to call the telephone operator's customer service hotline: China Unicom 100 10 and China Mobile 10086 for feedback, and ask the relevant departments to check whether it is a local network problem and go to the business hall to test the SIM card.

Fourth, if operators are excluded, then it is the problem of mobile phones. It is suggested to get in touch with iPhone after-sales in time and settle it through negotiation.