Why doesn't the subdomain open if you first opened it in the browser and then just created it and opened it again?

Question

linux

This is how it goes.
My job involves creating many subdomains. And sometimes I forget to create some.
I open subdomain sub555.mydomain.ru
Naturally writes 404 Not found.
And here I remember that I did not create it and create it through cPanel.
And try to open again. Writes again 404 Not found.
And if you open it through a hundred, then it opens!
I even tried flushing the Windows DNS cache via ipconfig /flushdns. Does not help.
What could it be for?

Answer 1

Well, you haven't cleared everything. For example, the browser also "remembers" your previous requests.
Next, you need to clear the cache also on your DNS server, which is registered in your network settings. Otherwise, he will give out what he gave out earlier.
If you need to create and delete something often, it's better to edit hosts

Answer 2

because the first time you opened a domain, you cached it on your dns server of your internet connection, most likely it is your provider's dns server, or google (8.8.8.8).
so you have to wait until the cache is reset there.