Some artists dissapeared from my liked songs

[ivanfbf]

I had several hundred of liked songs from dozens of artists. However, during the last days some songs from ONLY certain artist have disappeared from my liked songs, even to the point they reappeared in my "discover weekly" playlist. When I go to the artist page, they effectively are not liked.

Why are they missing? I do not think I've reached the 10K liked songs limit.

Thanks in advance

Ivan