Why is there a question mark on the text message and how to eliminate it?

Just resend the wrong message or explain to others what the problem is.

SMS is a part of unified communication service plan. Users can directly send or receive text or digital information through mobile phones or other telecommunication terminals. The number of characters that users can send and receive short messages at a time is 160 English, numeric characters or 70 Chinese characters. Short message is a telecommunication service in digital mobile communication system. It is a non-real-time and non-voice data communication service to transmit text or digital short messages through the signaling channel and signaling network of mobile communication system.