Sydney theme running very slow after fix

I recently had my Sydney them break on me after updating the YOEST SEO plugin. I paid to have it fixed,
and they said that they had updated the theme. But now the site runs very slow. I paid for one month of repair service, which is now over. Will updating to the Pro version of Sydney help? I run a small number
of plugins to keep things as slim as possible. Any thoughts on known issues?
Site: www.monochromeimaging.com

Thanks, Daniel

Hello Daniel,

I’ve just checked your website with GTmetrix and it seems to be pretty fast, here is the report:

So have you already resolved this issue?

Kind Regards, Roman.
aThemes Support

I have used the GTmetrix you mention to test some of my pages, and get good results. But when I open
the same page on my computer, it takes way too long to load. This page takes minutes on my computer,
but gets a great score on GTmetrix.
I have no issues with surfing the web using my computer, but for some reason using my site is a real
pain to use. Even when I log into WP to edit my site–everything is slow and frustrating.

Hello Daniel,

But when I open the same page on my computer, it takes way too long to load.

Yeah, that page loads very slowly, I can see that. You can try to contact your hosting provider support and see what they say.

Kind Regards, Roman.
aThemes Support