Solved! Go to Solution.
Press your bixby button once to open bixby. Press the magnifying glass to search bixby and type spotify. Click the spotify app and do you have the option to add/remove. If this capsule is missing then that is your problem.
If it is there try removing it and installing again.
Hope this helps
Are you in the US? It looks like its not available in some regions yet. (I guess i should have said most, this is horrible that Samsung still hasn't included this feature for other areas yet)