How to cancel Unicom's missed message reminder service?

Unicom's "Call Manager" is a communication assistant service for reminding and managing missed calls. When the user's mobile phone is turned off, there is no power or signal, the phone will be transferred to the voice platform of the call manager, and the call manager system will pick up the user's phone and send a short message to remind the user of the missed call.

Cancellation method: send SMS 0000 or 00000 to 10655766.