Need suggestions 
Somehow my phone was marked as stolen remotely. The siren was going off and it was repeating the message that phone was stolen. I woke up and put my in to turn the siren off but I am not sure why or how the phone was marked as stolen. My SIM card was not removed, and it could not have been access through my email as I have 2 step verification. Does anyone have any ideas on how this happened or why? Any suggestions on how to keep it from happening again. I have a Galaxy Note 5, and the avast version is 4.2.0.8278
Thank you,