I frequently back up my iPad Air 2 to my iPad Air 1 and iPhone 6s Plus, keeping everything up to date. I also make email and Dropbox back ups too. All my devices have iOS 9.1 installed. I use Airdrop to enable the back up process and up until today the process was seamless. Now, when I use Airdop or my Dropbox/email to back up, any new playlists are not transferred to any location or device. I added a new playlist with one new song to my iPad Air 2 (my default device) and it is missing after backing up, on all my other mobile devices and locations. I have 18 playlists. It seems adding one more is one too many. I tried deleting one and adding the new one but it didn't appear on my other devices either. Have tried resetting everything and re-downloading the app. No joy. I use this fab app for all my pro work. Please help!!

Many thanks in advance