Galaxy S5 :: Samsung Not Reading Artist Name For Only 21 Tracks Out Of 1300+

So I've been using file properties and windows media player to organise my music library and after the initial struggle of changing from iPhone to Samsung the last 10 months have been a breeze. Last week I decided to play around with some of the album art for albums that were showing up blurred in my lock screen. After changing a lot with Album Art Grabber, none of the current offending files, I checked to see the results and a few were still blurred so I decided to scrap that idea and with too many to pick through I just simply removed all music files and then but everything back to on my phone via drag and drop as per usual. Then I noticed there were around 40 tracks being read as <unknown> artist and a few were the track titles aren't being read also. Everywhere other than on my phone the tracks are correct and perfectly organised. I managed to get this number down to 21 but for the last week I've been having trouble trying to rectify the remaining tracks to no avail.

When things like this happen I wish I had an iPhone still but right now I would just really like to go back to last Sunday and not do what I did.

I've tried a couple of apps to edit tags from the play store but that hasn't worked at all.