Maybe there's a glitch in the app. Sometimes these things happen and you just have to wait for an update to fix it.
It might be because of copyright issues or your internet connection. Sometimes, if the music you want to add isn't licensed for use on Instagram stories or if your connection is unstable, it won't work. Try a different song or check your wifi/cellular data.
Maybe it's a glitch in the app. Sometimes these things happen and it'll sort itself out after a while.
Maybe there's a glitch in the app or your device settings aren't allowing it.
Maybe it's a technical glitch. Sometimes the app has bugs that prevent the music feature from working properly.
Maybe it's a technical glitch or a problem with your app version. Try updating the Instagram app and see if that helps.
It could be that the music rights are restricted in your region. Also, make sure your account settings allow for adding music to stories.
It could be that your Instagram app is outdated. Update it and see if that fixes the issue. Also, make sure you have enough storage space on your device.
Maybe it's a technical glitch. Sometimes, the app might have temporary issues that prevent the music feature from working properly.
Maybe there's a technical glitch with the app. Try restarting your device or reinstalling the Instagram app.
Another possibility is that the music you want to use isn't available in Instagram's music library. Instagram has a limited selection of music that can be used in stories. Try choosing from the available options instead.
It might be that your internet connection is weak, affecting the music playback. Or, it could be that the music you chose isn't compatible with Instagram stories for some reason.