I've noticed a lot of my older purchased music on Amazon Music is now unplayable without any notice to me. Usually the complete album is gone but sometimes it leaves me with just a few of the songs still playable from the album.
Often, these giant tech companies will happily make it so you cant get your songs or play them on the devices you want to: https://arstechnica.com/information-technology/2008/04/drm-s...