I have had this problem since 2012 same as you. I have talked to genius bar several times and Applecare, many times, and they have never admitted any issues. I show them some of these discussions, and they say there is no proof. Then I show them it doesn't work on the store's network and they blame it on Avast and other software, then they offer to send in my Mac for a week to have it looked at! Like I can do without my Mac for a week. They closed my cases but never solved them...very disappointing. FYI, my wife bought a 12" MacBook and my magic mouse works fine with it, but still not on my 2012 MacBook Pro. I just can't believe they don't know about the problem. They just don't want to pay to solve the problem.