First of all, I have already seen this question, and my question is not a duplicate of that one. In that question, the OP said he turned off his Facebook chat and his friends still see a green dot next to his name. My problem isn't about the green dot. Also, I have already tried the answer to that question, and it doesn't solve my problem - in fact it is the problem.
My problem is that when I go to Facebook on a desktop PC and open up the "Advanced Chat Settings", it is set to "Turn on chat only for some friends" and I have only one friend in there (not my mother). In addition, the chat bar on the right side shows my one friend, and then below that it says "These friends can't see you on chat" and shows all my other friends including my mother below it. But I just noticed on my mother's Facebook, her chat window still shows my name along with the last login time (21h) and the mobile phone icon.
Why is Facebook showing my name in my mother's chat window along with my last login time? My chat is supposed to be turned off for her, so shouldn't Facebook NOT tell her my last login time?
I thought this might have to do with the fact that there was a mobile icon next to my name in her Facebook chat. I do have the Facebook app on my phone, but I just checked it, and when I press on that gear button in the upper right corner, it prompts me to "Turn On Chat" or "Cancel". That tells me that chat is turned off in my Facebook app, so that can't be the reason for why my mother sees my last login time in her chat window.
So why is Facebook showing my last login time to my friends who are NOT on my "Turn on chat only for some friends" list?