Album art not appearing on Local Files

[0e61_nqyw-5tj]

Plan

Premium

Country

USA

Device

(iPhone X, and Mac Book Air)

My Question or Issue

Attempting to transfer local files on my laptop to phone, but the album art is absent once on my phone. The art is shown on Spotify on my laptop but only once the Spotify on my phone is closed, when both my laptop and phone are running Spotify the art appears as a black screen. I'm not sure what the problem is, I have transferred numerous other files without this issue of the album art not appearing. 

[Convoy501]

Additionally, The artwork shows up in playing view and in the

playlist for desktop.

[christian2008]

some of my song covers are not showing even after changing the resolution of the covers and file type. but some of the covers are working (I have been using mp3tag)