Minecraft

I explored half of a map earlier, holding it in my hands the entire time, and about 40-50% of it was filled in. I then explored a ton of stuff, etc. and then later quit the game.

But then when I returned later, it was blank again except the small circle where I start. My progress saved, it's just the map that is back to near empty again.

What's the deal?

singleplayer? multiplayer? using any mods? I never had a problem in my SSP.
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Like it or leave it. Hey, where are you going?

weird issue,i never had this problem before o.O
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when someone told you to "lrn2grammar" on gamefaqs,its SERIOUS BUSINESS
soulcalibur V = most disappointing game so far

SSP, no mods at all. Just the plain 1.2.5 game.