Disconnecting Error WOW51900319

I was doing a world quest in Bastion on my main (not this toon) and fell through the ground/floor. It disconnected me from the game. Now, every time I try to log back in on my main, it shows me still falling, then disconnects me with the same error message: WOW51900319. Help please.

https://us.battle.net/support/en/help/product/wow/197/834/solution