I'm trying to retopoligize my mesh. But my retopoligy mesh is acting glitchy where the mirror modifier meets. I have clipping turned on, so that my mirror modifier will connect. It seems to work ok on flat surfaces, but where there is a dip in the mesh, right where it needs to mirror, the mesh isn't connecting to the mirror, and its overlapping and acting glitchy.
(See attached images and video Link)
Does anyone know how I can fix this? Thanks!