[Решено] An error occurs when navigating to pages in the admin panel

Tell us what you are trying to do?
I installed a new version of WordPress. the site opens, but I get an error when going to the pages in the admin panel. I also updated the theme.

I haven’t been able to get normal help from you for two days now. I have an open ticket with Christopher Amirian. he answers very rarely, I have already done everything he asked. can you take care of my problem please?

What is the link to your site?
скрытая ссылка