iphone 8 album art problem

I have a 256gb iPhone 8 plus that I have been trying to use as an ipod as well. I put over 70 gigs of music on it with no problems at all, but now when I have tried to add more it is fine taking it but it displays artwork from other bands on each album and does not have the artwork from the albums as I have presented them, though the artwork on each file is clearly correct. This has been going on for a few days and the photo I present gives a little idea of what I am talking about. This is highly frustrating and I have no idea how to fix it, any info would be useful.