Alarm how to Stopped? "Antitheft" IMPORTANT!!!

@VilleBest Ville, I have a problem with the new option Anti Theft.
 My Fs protection i had installed in a mobile from an friend. Then we started testing the new option Anti Theft. I used the option "Alerm" and the alarm go on on his mobile. But the alarm is not stopped, also if he put a button on his mobile. He continues to ask for a password to install the app. We have no password set for his cellphone. Is there a default password, or how to stop this alarm? It concerns the "LG D722" in my account. Was also tested on my mobile but it works well and is set just off the alarm. I like to hear what to do. Is it an option to remove him from my account, that im removing the license from his mobile?