Playlist syncing issue

[Hirquliz]

Plan

Premium

Country

canada 

Device

(iPhone 7 / new ipad / PC)

Operating System

(iOS 10,Windows 10,etc.)

My Question or Issue

 I started with a playlist on my iphone 7 and had download turned on and had about 300 songs on this playlist. i then used my ipad and PC and add more songs (about 250) to the playlist and the playist is completely downloaded to my ipad and pc (about 550 songs), but my iphone still says 300, i tried logging out and logging back in, nothing happened, i tried turning off 'download' and then re-downloading it. still not updated with the rest of the songs.... i use my iphone for 99% of my spotify use so this is frustrating....any ideas?