It looks like you have it working with having both a nurbs and poly object in your pic..
Go to modify> center pivot then move the poly object out of the way and delet the nurbs object under the new poly. Move back the poly object into position.
If you still cant get it zip up the file and post it and i'll have a look in the morning.
Kurt
I am enough of an artist to draw freely upon my imagination, knowledge is limited, imagination encircles the world. (Albert Einstein)
https://www.artstation.com/kurtb