Have the exact same issue. Noticed it first yesterday through Android Auto that they had disappeared and they are still missing this morning on my phone. Haven't tried anything crazy like re-installing.
However, yesterday there was also an issue where the music would pause randomly while the screen was locked and resume when I hit the lock button. Force stopping the app stopped that. Not sure if that would be related at all but it was odd and around the same time that all this started happening.
Thanks for posting about this here in the Community!
If you're having troubles locating your Daily Mixes in the Made for You section or when you search for them, we'd recommend adding your +VOTE in this ongoing issue. Rest assured that our tech teams are looking into it so we'd suggest keeping an eye out for updates on that thread.
On another note, @user-removed, you mention that music pauses randomly when locking your device. This sounds like a different issue than the one described in this thread. If the issue persists in the future, we'd recommend taking a look at the steps in this support site article first.
Hope this helps clarify things! If there's anything else we can help with, don't hesitate to give us a shout.
Have a lovely day 🙂
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