Borean Tundra Map Bug (Unplayable)

I have a problem, rather big one.

I reached Borean Tundra in Warsong Gulch, all good so far.

I step out of Warsong Gulch and start randomly falling under the map. At first I thought it to be a simple bug, I resurrect, walk around a bit more and it happens again. I can't continue questing in the zone.

I continue falling through the map every few seconds.

Any way to fix this? Thanks.