Excuse me, what happened to the message you received without the sender and number?

Now there are many sp as SMS relay stations, so you can find a service that provides hidden numbers, usually with a special service number before the destination number.

For example (a long time ago, I don't know if it is applicable now): For example, if you want to send a short message to your friend 137 12345678, but don't want him to see your mobile phone number, edit the short message and send it to 09282 13765438 (that is, add 09282 before the number).