Hi guys!

I've got strange problem when I'm using Warp Tool. I want to make flag from my shape, but when I apply wrap effect which do this, I get two vertical stripes. Just see the image below:

(To see cause of my problem, please see picture in high resolution)

I've got sam issue, when I use Wave, Fish and Rise styles of Warp. With other - I don't have that problem...  
Could someone can help me with that?

Greets!