Why is the letsencrypt certificate considered invalid?

Question

linux

I did it according to the instructions , but accidentally did not make the first item with .well-known , after which I added a single file and updated the certificates.
A message popped up saying that everything is OK

. I restarted nginx, I try to connect to the site and I see that the certificate has been updated (I did it according to the instructions yesterday and the certificate expired on September 26, here it is 27), but it is still considered invalid ... How to confirm it?
nginx config example

server {
    listen 192.168.47.64:80;
    server_name example.com www.example.com;
    # enforce https
    return 301 https://$server_name$request_uri;

    if ($scheme != "https") {
       return 301 https://$host$request_uri;
    }
}
server {
    listen 192.168.47.64:443;
    server_name example.com www.example.com;
    ssl on;
    ssl_certificate /etc/certbot/live/example.com/fullchain.pem;
    ssl_certificate_key /etc/certbot/live/example.com/privkey.pem;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

    location / {
        root /srv/www/example.com;
    }
    include letsencrypt.conf;

 #   if ($scheme != "https") {
  #      return 301 https://$host$request_uri;
   # }
}

Error in the browser

Information about the certificate

I don't know what it can give you
SSLSHopper check result I

looked through the line with the test server in the config settings... The problem is solved, thank you all!!

Answer 1

Why is it considered unreliable? what error does the browser give?

Answer 2

The problem with the date is possible due to the skewed time zones, as an option. And unreliable may be due to incorrect configuration of the web server. In the spring I had a problem in Opera new.
If I'm not mistaken, then there is an option to revoke the certificate and create a new one. Or stupidly create a new one.

Answer 3

https://community.letsencrypt.org/t/sec-error-unkn... read?
I had a similar problem, but with iis https://community.letsencrypt.org/t/iis-8-5-buildi...
the problem was in the mismatch of the chain of signers and was solved by replacing them.