Its very difficult for someone to talk on the phone if your talking louder than the caller at the end of the line. Keep asking them very simple questions and explaining to them what is going on. Eventually they will find it impossible to carry on their conversation................its always worked for me.
Pin pointing a phone is difficult, if its in a locker open them up til you find where it is coming from. If its on them you should get close, you might find pax around will help you.
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