Most common issues can be fixed with a quick reinstall of the app. In some situations however, a clean (more thorough) reinstall of the app might be needed. This way, you can start afresh with Spotify on your device.
Below you can find all the steps for a clean install of Spotify on your device - just scroll down until you see your device/OS:
The steps for a clean reinstall in an iPad device are similar to those of iPhone devices above. Keep in mind that in step 4 you'll need to look instead for iPad Storage.
Tip: If you'd like to be more thorough, you can also use in addition a trusted third-party device cleaner app to make sure you've removed any leftover files before installing the app again.