I know it sounds simple, but it's often overlooked. Could you try restarting your device? If that doesn't help, try a quick clean reinstallation of the app. Just follow the steps here. Also upgrade your iOS, the latest version of which is 11.4
If you're still having trouble, could you let me know the exact version of Spotify and the exact version of the operating system you're running?
I'll see what I can suggest!
LoxerRock Star 16
Help others find this answer and click "Accept as Solution".
If you appreciate my answer, maybe give me a Like.