I bought a new template, but the authors never responds to my "ask for support" emails

Can any freelancer fix it if it is problem with theme, or this freelancer must have that theme and theme license?

I have problem with Olars theme, it was updated 19.06. as it states on Envato market and after that day my website is half black on desktop. I contacted theme designer but no reply in two days.

And also what is considered customization?
if I changer content of the theme - text, photos, menu item, is that customizations? I mean, that has to be done to make website for yourself.