Okey, after facing this problem over and over for some years now, I come to all of you with an ultimate solution that will work regardless of whatever problem you're facing with music tags.
This problem occurs because iTunes is poorly coded and uncapable of fixing songs ID3 tags, which means that even if you try to upload your songs using iTunes Library and fix their tags one by one, you will still be getting this issue once iTunes does not handle tags properly and does not know how to fix them for you.
The solution is to download an alternate ID3 tag editor and re-write all your songs tags in order to iTunes (dumb) to be able to read them on its own poorly coded way.
Solution:
I'm using a Windows based system, so i've downloaded a free softwared named Mp3Tag ( https://www.mp3tag.de/en/ )
After that, all you have to do is:
01) Open Mp3Tag
02) Go to: Tools > Options
03) Expand Tags > Mpeg
04) You will face the following window: https://imgur.com/a/VBHIc
05) Check the boxes exactly as you see in the picture
06) Load ALL your beloved songs into Mp3Tag, it will look like this: https://imgur.com/a/uHI2F (Search google to find out their location on your computer)
07) Check the tags and fix any missing infos on Title, Artist and Album Artist: https://imgur.com/a/dCsmq
08) Select all the songs (COMMAND+A on Mac or CTRL+A on Windows) on Mp3Tag and hit the save button: https://imgur.com/a/yCZpm
09) Remove or unsync all songs from your iPhone and re-upload or resync them back.
10) Done! See the magic happens.
P.S.: I myself am using the option "Manually manage music and videos", but if you're not, you can still "Sync" them again to your iTunes Library and then to your iPhone. If you don't know how to do that, search google for more info.