How To Turn On Sync Library On Iphone, i don’t know what to do sync library doesn't show up on my iphone, and I have Itunes match So frustrated: sync library doesn't show up on my iphone, and I have Itunes match. Maybe you should try deleting the app, reinstalling music, and then selecting turn on library from the app’s Turn off Sync Library. On your iPhone, go to Settings > [your name]. Sync Library keeps your Apple Music library consistent across all your devices. Learn how you can turn on or off sync library with Apple Music on the iPhone 13 / iPhone 13 Pro/Mini. If you can sync as expected after double T