Subscription changed

[Dealertify]

I've been out of my country for the last 6 months and a couple weeks ago it showed when I was trying to start the Spotify app a message saying I can only use Spotify 14 days abroad. I tried many time to login and this message kept popping out. So I finnaly am home and I manage to login but know from a premium account I have a free account!! Apart from the stupidity of not being able to use Spotify abroad why did my account changed from premium to free if everything required is in order.