How do Unicom users open SMS calls through SMS?

At present, Unicom users can't open SMS call transfer service. If you need to set up call forwarding, you can set it by entering the operation instruction and then pressing the call button. At present, there are four call forwarding functions, 1 and unconditional call forwarding: operation instruction **2 1* number # dial call button setting; 2. No answer call forwarding: operating instructions **6 1* number # dialing and call key setting; 3. Call in case of busy: set the dial key of the number **67* in the operating instructions; 4. Call forwarding cannot be turned off: operating instructions **62* number # dialing and call key settings.