Apple's dual-card registration of WeChat failed to send SMS.

1. It is possible that the interception software of Apple's mobile phone positioned the registered micro-signal as spam, so the sending failed. The solution is to add the number to the address book, edit a name casually and save it, and then send the registered WeChat message, which can solve the problem.

2. Apple phones sometimes have some incomprehensible problems, just like computers, just restart them.

3. If it still cannot be solved, it may be the operator's problem. You can wait a few hours before sending it or contact the operator's customer service for advice on how to solve it.