Map in the background disappears

Hi! I recently uploaded a map of Thundertree in my game of Lost Mine of Phandelver, but everynow and then, it disappears.  The tokens are still up to date, as the images I set in the background for "visual improvement". The fog is the unchanged too. I checked with Safari, Chrome and Firefox, same results. I checked on a different computer (laptop/tower), no map.If I put a new map on, the visual improvements will disappear. Anyone know what's up?

I have had map images become corrupted before this may be what is happening. When you upload an image to roll20 it creates multiple copies in different sizes and occasionally these will become corrupted. I have had ones not fully render and stay blurry, never one that disappeared. Try deleting the full image from your user library and re-uploading it. Let me know if that works! 

Hi Brian! Weirdly enough, everything came back right now (didn't work 5 minutes ago!) so, hummm... I guess it's ok...?  Could it still be the image being corrupted? Fortunately enough, LMoP became free as of today, so I might have an alternative if my map does it again!