I couldn't transfer music files from my Samsung Galaxy S9+ to my MP3 player using theISB cable and connector. It's only charging the MP3 Player but it wouldn't let me switch to phone to carry out the transfer. I've done it before and it was ok, but now it won't allow me. I don't know what's wrong. Each time l click on phone, it says couldn't switch and it remains on USB Connect which only charges the MP3 Player.
Same thing happened on my S9+ even without the usb flash drive attached to the connector. Been scouring the internet for a solution but this is the first post I'm coming across. I've got an Huawei P20 mate and the same thing has happened so I think this is down to the recent updates. I've four different connectors and it's ihe same. Can't switch from usb device control to phone control and on the P20 mate it just switches back and disappears. Any solution is very much welcome.