Who sent the call reminder message?

I have also started this service, so take me as an example: when I turn off my phone, you will hear "the subscriber you dialed has forwarded the call to the call reminder service, and your phone number will be sent to the other party's mobile phone in the form of SMS". . . When I turn on the computer, I will receive a message "You sent it", which is probably "/kloc-0 150xxxxxxxx ..." Although it is "you sent it", there is no information fee.