Well, that would appear when the effect can't determine the internal fold direction of the deformation, i.e. whether to displace horizontally or vertically first. Use the starch and overlap tools to control that a bit. Otherwise your mesh or your imagery may need tweaking, but without seeing those nobody can advise.
Unfortunately your screenshot tells us nothing about your timeline or your layers so I can only guess that your mesh is too small and you are moving the puppet pin in a way that is causing the mesh to fold back on itself.
If you want better answers give us a full resolution screenshot showing the layer that is giving you problems in the timeline with all properties revealed (press the u key twice) and the comp window with the mesh revealed. That will give us an idea of what you're doing.
Thank you, Rick and Mylenium, I was able to figure out the issue at least for this situation due to your posts, It seems my bend it effect which was unnecessary at this point in the animation was actually the cause of this.
again thank you for your help.