has anyone work with a theme called vimes from wpzoom

well anyway I’m having this problem with the thumbnails of the portfolio. some of them show up and some don’t. I have followed the instructions on the wpzoom forums and tutorial video but they don’t seem to help either.
so please help me out ??

my url is https://www.candidavenue.com

here is the demo of the theme to compare it with –

https://demo.wpzoom.com/vimes/