There is no signal on Apple's mobile phone, and the short message was not sent successfully. Is there a signal that will be sent automatically?

There is no signal on Apple's mobile phone, and the short message was not sent successfully. When there is a signal, it will not be sent automatically. According to relevant data, Apple's mobile phone failed to send information, which was caused by poor cell phone signal. You can change the location or turn off the phone, restart it and send it again. Apple's mobile phone doesn't automatically send messages, so you need to resend them yourself.