After it's uninstalled, go to the Google Play Store and download Spotify again. Find Spotify on the list and then tap ' Clear Data/Cache' and then ' Uninstall'. If you're using Android, head to Settings > App Manager (The name of the option varies depending on the brand of your phone, but it should be something like that). When you log back in, all the storage it was using will be freed. Once it's deleted, go to the App Store and download Spotify again. Then, tap the small ' X' and delete the app.
If you're using an iPhone, tap and hold on Spotify's icon until everything starts shaking. What is your device? You can free the space spotify is using by performing a clean reinstall.
