itunes syn greyed out. apply in place.

You will need to check the Sync settings for the phone (each device has its own sync settings).

If you have Apple Music turned on in your library or on the phone, that will affect the sync.

• Once that is off and the phone is seen in your iTunes, go to Device/Settings/Music pane (1. in the screenshot below) and make sure that the Sync Music button (2.) is ticked (checked):

• in section 3., if you have chosen to sync:
  • Entire music library (3.), the all the music in your library should be added to the phone
  • Selected playlists, artists, albums and genres (3.), the you need to choose items in section 4. as well

If you make any changes as noted above, click the Apply and/or Sync button for the changes to take effect.

Have you tried tapping the Apply button? If so, what happens?