Iconmoon "Strokes get ignored when generating fonts"?

Question

Fonts

I sent a set of svg icons to dis, I'm trying to make an icon font in Aikonmun.
Half of the icons don't work, writes "Strokes get ignored when generating fonts."
What is Strok I roughly understand.
How can it be repaired? Or are they shit icons and need to be changed?

Answer 1

Faced such a problem.
I can not give a universal solution, but I changed the icons.