Too many folds lasting slingback pumps

Hi Mrs. Sveta.

I’m working on a slingback pumps and I made a paper pattern just like you teach in your lesson. You can see in my video clip that when I last it, there is too much fold in the bottom and it looks bad. I can see that your pattern is flat , so I guess I am doing something wrong. If I pull the strap higher it makes it better with less folds, but I am pretty sure that it is not something I need to do, or can I? 
It’s 4 cm heel and I lost my original cardboard pattern. How can I fix it? and do I need to start all over again or can I use this paper patern?
Thanks in advance,