Song or album is grayed out, and cannot be selected or played.
Here are some reasons Amazon Music Unlimited titles no longer show as available:
The titles were removed from the Amazon Music Unlimited catalog.
Your Amazon Music Unlimited subscription expired or was canceled.
You haven’t used the app while connected to a wireless network in the past month.
You have recently updated the Amazon Music app and need to redownload your music. All your offline music will be re-downloaded in one go when you select the Download option. If you do not have a Wi-Fi connection currently, you can select the option to download when Wi-Fi is available and the download will be queued.