I can't install Chocolatey

[DaimonCity]

I just had followed that instruction: https://chocolatey.org/install.
But, when I had tried to download https://community.chocolatey.org/install.ps1, I got the error:

Exception calling "DownloadString" with "1" argument(s): "The underlying connection was closed: An unexpected error occurred on a send."
At line:1 char:166
+ ...  -bor 3072; iex ((New-Object System.Net.WebClient).DownloadString('ht ...
+                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : WebException

I have searched information about it, but nothing has helped.
So help me, please

P. S. Simply things like "Start as Administrator" or Execution Policy I checked more times.