Sharing music on my Instagram stories is not an option for me. I have been using Instagram for 3 months now and the option never popped up on Spotify, though I have been paying the same amount of money that everyone else has. I have already tried uninstalling/reinstalling/updating both apps numerous times. I'm attaching some screenshots.
PS: Please don't link me to the "We're always testing new things to improve your experience!!!!!" page, it's not a new thing. Everything is up to date.