Unbinding mobile phone in perfect space-time

Unicom users write a short message "997" and send it to106688880411,and they will receive a short message "Reply to the short message 998 1 Confirm that the phone and account are unbound * * *"; Telecom users write the short message "10 1997" and send it to 10668885, and they will receive the short message "Reply to the short message10/9981Confirm that the mobile phone is unbound from the account * * *". The binding function of mobile phone can only be released after replying to SMS.