Q: Downloaded song are missing in my liburary, I bought and downloaded songs. and only some songs are available in my library and others I can't add them or download them.

Howdy lperez6,

Thanks for using the Apple Support Communities.

If you're trying to download previously purchased music from the iTunes Store, then they might no longer be available in the store and available for redownload.  For more information please see below:

Before you can access a past purchase, you need to do the following:

1. Sign in with the Apple ID that you used for the original purchase. Use these steps to see which Apple ID you used to download an item.
2. Check to see if the purchases you're looking for are hidden. If your purchases are hidden, you might not see them even after you follow the steps below. Learn how to unhide purchases.
3. See if the content is available for redownload. Previously purchased items might not be available if they're no longer on the iTunes Store. Also, make sure that you’re in a country where you can redownload items. If you changed your Apple ID from one country to another, you can’t download items you purchased in a previous country.

If you're a member of Apple Music, items that you've saved for offline use won't appear in your purchased section. Learn more about Apple Music.

Download your past purchases

Take care.