I was on Avast website the other morning and I put in my pnone number for antitheft, now my phone keeps saying "this phone has been lost or stolen" and there is a loud siren coming form it. I have no idea how to turn it off and now I cant use my phone. it is a Galaxy 3 phone. Can anyone help me to turn off this siren, I have tried emailing but no one is answering my emails. Please someone help