iTunes OS X Music and Playlist

Hi there Rodolpho Favaro,

It sounds like you aren't seeing any of your iTunes content in your library but it is showing just fine on your iPhone. If this happened after you updated your iTunes application then I would use this article to help you out:

If you don't see your content after updating iTunes

You may also just need to sign back into iTunes Match on your computer:

Add your computer, iPhone, iPad, or iPod touch to iTunes Match

1. Open iTunes. Make sure you have the latest version.
2. From the upper-right hand corner of iTunes, click Sign In. Enter the Apple ID and password you use for iTunes Match.
   
3. Mac: From the menu bar at the top of your computer screen, choose Store > Turn On iTunes Match.
   Windows: Press the Control and B keys on your keyboard to turn on the iTunes menu bar. Choose Store > Turn on iTunes Match. Learn more about menus in iTunes for Windows.
4. Click Add This Computer.
5. When prompted, enter your Apple ID password again.

iTunes will match and upload your library. You can watch the progress of the matching and uploading in the iTunes LCD, and you can pause and resume this process at any time.

When iTunes is done, your music in iCloud will appear in to your local music library. A download button appears next to any content you have in iCloud that isn't on your computer.

Thank you for using Apple Support Communities.

All the best,

Sterling

You are correct, I missed that detail. due to the nature of this issueyou may need to contact Apple with the following resource for more help - https://getsupport.apple.com/GetproductgroupList.action.