iPhone app keeps syncing my playlist all over again

[Ascansio]

I've been using Spotify on my PC and iPhone since May 2014. Not any single problem occured until the last week actually. But since last week, everytime I launch my Spotify app on my iPhone 6 Plus, even though it's already synced for offline availability, the app starts to synch all my playlist again from stratch. And it repeats this process everyday now, deleting all the synced music data and start to sync them again like it was never synced. What's confusing my app, is there any solution to this? 

[MattSuda]

Have you tried reinstalling the app and then syncing the playlists again to see if that solves the problem when you open the app up again?

[Ascansio]

Absolutely, I reinstalled my app, even reinforced that method with updating my iOS to 8.2 also, but that didn't changed anything at all.