unknown album/unknown artist

I've put the necessary information.

Song name

Artist

Year

Everything is the same as the named album, yet it won't merge the two. It also displays as 'Unknown Album/Unknown artist'

Pretty stupid seeing as as far as I can see there's nothing wrong. What baffles me more is it's not even like it's making another album. No matter what I put in there it just says unknown album by an unknown artist, yet it CLEARLY does know the names because when i play the song or go to 'get info' it shows the correct names.

Help anyone? It's petty and means it won't play with the album.