Why is it that i cant get a response from Oukitel's anti theft?

[Android Central Question]

Its Actually My elder brother's phone,which the first time he changed the sim card and it locked,my number was his backup and i sent the #mima # code as a text and it replied the code,he entered it and it unlocked the phone,last night he switched his sims again and then it happened but this time i sent the code and nothing happen (about 9times) and then i tried the #suoding # which is ment to wipe the phone then that worked but it iwe still cant access the phone cause its still asking for an anti theft password which i dont have/wasn't sent,So what do i do in this case.