Why does the site not work on just one computer?

Question

Domain Name System

I am developing a website.
The work is almost coming to an end, I transferred the site from test hosting to the main one.
The site works fine for me and EVERYONE, and the client still has a REG.RU page when he enters the site.
He has already tried updating the cache and another browser, and no matter what he tried, nothing comes out.
Everything works on other devices. The problem is on the laptop.
Tell me what can be done in this situation?

Answer 1

Let dns-cache update.