Music not showin up

im not new to this but i put sum music n my cache like i always to it, and it usally works
but sumthin happened one day i wuz listenin to my music on random and somthin popped up cuz the music stopped and it wasnt a call or anything, so i pressed ok because i thought the music would play but it turned out it deleted all my music but i was in the music player section so i no i didn press delete music i just no it..
so i went back and put the music that was deleted back in the cache and its still there but it wont show up in my music playlist nothin is there but when i go to the cache when i connect it to the computer.. everythin is there.. what is goin on !! HELP MEH PLEASE !!