Tapered Trace function not working

Hi Guys,

im using cadence allegro 16.5 version. and for some reason the tapered trace function wont work on a selected cline?

i have attached an image with this of the issue and you can see why i wish to taper. the function says it has finished but the cline stays the same.

i know that there is a desired angle and tapered trace options in the settings for tapered traces but im not sure how this works? would anyone know the optimal settings to get this to work?

all help is welcome.Thanks

Regards

Fran