Trouble with the vertices of the edges of one sided polygon

TheCediz

Hello, I'm not sure if it is too much of a zbrushy question for Daz forums, but here we go. I am morphing some clothes on zbrush and I dont know much of the program yet. I use the move brush and it works fine exepted for the last vertices of the edges of the polygon. It is a real pain to work with ; they kind of dont want to move. 

Is someone aware of a brush or tool I could use to get around this lost of time??