Fiio X5 3gen always logged out in offline modus

[kk8132]

Premium

Switzerland

Device

Fiio X5 3gen

(Android)

My Question or Issue

I installed the Spotify Android app and downloaded some playlists on one of the two sd micro cards I bought for it. Then I put in the menu the "offline modus" and turned off the Fiio player. For using in the car I turned on the Fiio player and conected with thr bluetooth with the car. After using it I turned a second time off the Fiio player. When I turned on again, I was logged out from the Spotify app and I had to connecting with the wlan to sign in. But it was not possible. So I had to uninstall the app. After new installing it was possible to sign in. So I did the same procedure as described before. I have always the same problem that Fiio player looged out from the Spotify. Any ideas where the problem is? Thank you.