Why did I send a short message with my calling number? Why did the other party say I didn't receive it?

The other party did not receive the message for the following reasons:

First, the receiving time set by the other party's mobile phone is 1 day. If the other party's mobile phone is turned off or out of service area, and there is no signal during this period, you can't receive SMS.

Second, the network transmission failed. Your mobile phone has no receipt report, so you can't see whether the short message was sent successfully.

Third, some mobile phones failed to send, but the prompt was successful.