Tiles are displaying as a different color after switching to different platform.

I am having a hard time trying to figure out why my assets are not displaying properly. I had the project to build for mac, and I then switched it to android platform, and i created a apk to test the game and everything seemed to work fine, i closed unity and when i reopened it displays this. All the tiles are filled in with the blue color, i checked the assets folder and the preview also shows them as blue. I attempted to refresh, reimport everything, and no luck, I then reverted back to mac and another scene (different set of assets) had a pink filled in for some of the tiles. Im not sure whats going ?! has anyone experienced this?