music purchased in itunes or added from your computer will appear here

I opened the "Music" app and realized my music had disappeared. When I go to my library, I am prompted with "Music purchased in iTunes or added from your computer will appear here". I would understand if this only happened to me, but it also happened to my brother. My family shares a Apple Music plan, but for some reason only me and my brother are victims of missing music. Has this happened to anyone else? Is there a way to fix this and get our music back?

Thank you for your time