After one week, I came back without any notice and buzz the door ring. She answered but went to the opposite direction, in the meanwhile, she put the fall detector back her neck.

I was wondering why she did it and asked for the reasons. Just realized that she feels there is no point to wear it and  the device is a little bit uncomfortable to be worn. Moreover, she feel that the size of device just trigger other people's notice if she wears it. S