We can't share music with Family Sharing

On your iPhone, iPad, or iPod touch

1. Go to Settings.
2. Tap your name, then tap Family Sharing.
3. Tap Add Member.
4. If your child doesn't have an Apple ID, tap Create an Account for a Child. But if your child already has an Apple ID, tap Invite People. ... 
5. Follow the onscreen instructions.

Set up Family Sharing - Apple Support (IN)

we have family sharing

It sounds like you already have things set up, but it would help to know what messages you see or what exactly makes you think you cannot share music. I can think of half a dozen reason why you might have problems so more details would help narrow down reasons.

Note that you cannot share with users in another country.

Note that the music has to be items you have purchased from Apple. While Apple Music will store copies of music you have transferred from CD, it won't share those.

Sometimes it helps to have the devices involved take a fresh look at settings:

- Try signing out of accounts and back in again.

- Restarting is a simple step that can resolve many unexpected behaviors.

If a problem persists, particularly over several days, try contacting Apple for assistance:

Click here --> Choose your country or region - Official Apple Support Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

or:

"See a list of Apple phone numbers around the world."

Click here --> Contact Apple for support and service - Apple Support

This may also help you --> If you can't find your family's shared content - Apple Support (IN)