Ludlow slugs stuck in mold

My ludlow is not pushing the 12 point cast slug out of the mold.

I can cast a blank 12 point slug and the machine works great. I try to cast a line with two 30 point mats and the slug stops the machine.

I took the mold off and cleaned it with mold polish, will that help correct the problem. I have not had a change to try the casting again.