Hello @hugoroger,
I don't use cPanel so I can't help with that part but...
You are not using Let's Encrypt certificates, you are using certificates issued by cPanel and they expire on Feb 15 23:59:59 2017 GMT.
I don't know what you installed but I'm pretty sure that the certificates are not issued by Let's Encrypt, as I said they are issued by cPanel CA. Maybe you have not reloaded your webserver so you are still using the old certs issued by cPanel... anyway, I've checked the certs you have issued for your domains on https://crt.sh and I can't see any issued by Let's Encrypt.... maybe you have issued them recently and they are not yet uploaded/processed by crt.sh
Your site https://www.iforumelite.com
is showing a cert issued by cPanel, the "problem" here is that you have a redirect/rewrite rule redirecting https to http, pay attention to below output from your server, you will see a Location header redirecting https://www.iforumelite.com
to http://www.iforumelite.com/forum.php?s=7c01b777432f8d66d2f927f5d848aa88
curl -Ik https://www.iforumelite.com
HTTP/1.1 303 See Other
Date: Sun, 22 Jan 2017 03:03:07 GMT
Server: Apache
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Set-Cookie: bb_lastvisit=1485054187; expires=Mon, 22-Jan-2018 03:03:07 GMT; Max-Age=31536000; path=/; secure
Set-Cookie: bb_lastactivity=0; expires=Mon, 22-Jan-2018 03:03:07 GMT; Max-Age=31536000; path=/; secure
Set-Cookie: PHPSESSID=mu0439tjvvbn761r7fab3tr3q3; path=/
Location: http://www.iforumelite.com/forum.php?s=7c01b777432f8d66d2f927f5d848aa88
Content-Type: text/html; charset=UTF-8
Note: The redirect/rewrite rule could be in your apache conf, on .htaccess files used by your site or even the forum that you are using could be redirecting it.
Here you can see who is the issuer and the dates of the certificate being served for https://www.iforumelite.com
$ echo | openssl s_client -connect www.iforumelite.com:443 -servername www.iforumelite.com | openssl x509 -noout -issuer -dates -subject
depth=3 C = SE, O = AddTrust AB, OU = AddTrust External TTP Network, CN = AddTrust External CA Root
verify return:1
depth=2 C = GB, ST = Greater Manchester, L = Salford, O = COMODO CA Limited, CN = COMODO RSA Certification Authority
verify return:1
depth=1 C = US, ST = TX, L = Houston, O = "cPanel, Inc.", CN = "cPanel, Inc. Certification Authority"
verify return:1
depth=0 CN = iforumelite.com
verify return:1
issuer= /C=US/ST=TX/L=Houston/O=cPanel, Inc./CN=cPanel, Inc. Certification Authority
notBefore=Nov 17 00:00:00 2016 GMT
notAfter=Feb 15 23:59:59 2017 GMT
subject= /CN=iforumelite.com
DONE
If you want that http points to https you should create a redirect from http to https on your own, I don't know if cPanel provides a graphical or easy way to create a redirect or you should write it directly to your apache VirtualHost conf.
This one shows the same behaviour than iforumelite, you have a redirect pointing from https to http (at least on your main url)
$ curl -Ik https://www.clashforum.com.br
HTTP/1.1 303 See Other
Date: Sun, 22 Jan 2017 03:18:44 GMT
Server: Apache
Set-Cookie: bb_lastvisit=1485055124; expires=Mon, 22-Jan-2018 03:18:44 GMT; Max-Age=31536000; path=/; secure
Set-Cookie: bb_lastactivity=0; expires=Mon, 22-Jan-2018 03:18:44 GMT; Max-Age=31536000; path=/; secure
Location: http://www.clashforum.com.br/forumdisplay.php/1-Forum-Principal?s=576fa994c378962ab56079746da55e47
Content-Type: text/html; charset=UTF-8
Regarding https://www.clashforum.com.br/activity.php
you have mixed content, that means that you have some objects using http in a page that it is being showed as https. Open the site https://www.whynopadlock.com/ and in the form (Secure url) paste your url https://www.clashforum.com.br/activity.php
and check and you will see what are the objects that are using http instead of https, lots of them are images.
I think you should recheck your AutoSSL conf/doc carefully and also review the conf of your sites.
Good luck,
sahsanu