Portfolio shape hexagon not really an hexagon




I need some help with my wordpress customization.
I installed angle theme & I wanted to test it before apply it in production.

I created one page & I added throw Visual composer the portfolio item.
No problem until I launched the page preview.

The hexagon icon for my portfolio items don’t look like an hexagon…
It looks like one hexagon with triangles mixed…

How can I resolve this please?