mi(cover) formula returning as blank

When I try to use the $mi(cover)$ formula it returns blank in all Kustom apps on version 3.45b7815. The only way to get the album art is to get it from the music player notification by using this formula $ni(mi(package), bicon)$

Maybe is a problem with your music player, you can test other like Google music and see what happen.

I saw this post and it seems that setting the option to set it as the lockscreen in my music player fixed the issue. I think I might of turned it off by accident because there isn't any way to know on One UI because it doesn't show the art on the lockscreen.