Instagram is providing the feature of adding music to Instagram Stories. If you want to make your music available for the public in the app, you must distribute it to Facebook Rights Manager.
Instagram is linked to the Facebook Rights Manager catalog, from where the application gets the music that you can find available for sharing in their users' stories.
You can check the first step in knowing how to add a story or how to add music in the story going to "What are some tips for uploading, recording and editing my story?".
The releases that you distribute to FRM are also monetized through your La Cupula Music account. However, the monetization of this channel takes longer since it is annual.
If your songs are not displayed in Instagram stories but you have previously distributed them to Facebook Rights Manager channel, please, contact email@example.com.