I have a similar problem as discussed here:
I accidentaly removed the "Liked from Radio" playlist (Radio-Favoriten in german).
I tried to restore it from the account page and deleted all the songs from it.
Unfortunately I still have songs from my mixes as "liked" also the "Radio-Favoriten" playlist is completely empty.
Furthermore, if I like new songs, they are not added to a playlist.
I guess my playlist is currently not linked to this feature anymore and I do not know how to recover that functionality.
Thanks for any help,