Most modern phones can't use the message reader, it's something to do with the type of Bluetooth they use, I'm sure other people on the forum have better knowledge than myself on this matter. I've tried android, apple and windows phones over the years with up till recently windows being the best as cortana would read out the sms messages over Bluetooth.
Cortana would also appear in your phone directory so you could call her and get her to send sms, ask local weather etc but this was via Bluetooth and not truly using the B&M.
If you look at my post on the samsung galaxy s7 you will see I have finally managed to use the message reader but I'm at a loss as to explain how, I think it's to do with a sumsung update for wifi calling that may have altered settings.
Sorry I can't be of more help.
