Premium but offline not possible to switch songsd backward between the songs

[Lies1234]

I'vo got a premium account and downloaded a few playlists. When I activate the offline mode to play and turn off the internet on my phone I can't use the forward and backward button to switch between songs. When I push the forward button spotify give a popup with the option to go premium (what I already have).
What is possible is choose an other song in the playlists..that's strange behalve that is a premium function too.
Does somebody have a solution?

[Joe]

Seems to be a bug when upgrading to premium as reported here. Reinstalling the app following the steps here will fix it.

Unfortunately, you will need to redownload your music.

[Lies1234]

Tnx Joe for the solution. I will give it a try.