CF7 No longer send e-mail. Tested manny things!

Contact Form 7 stops working. Instead of showing the message below the form, it reloads the page with form data in the URL and does’t send the e-mail.

I already deactivated all plugins, tested with another theme, downgraded WordPress and CF7 versions, but it doesn`t work either.

If anyone could give me a light on this, I will be deeply thankful!

Here`s the details of my installation:

=== Diagnostic Glance 0.9.1 ===
WordPress Version: 4.9.6

== Listed Themes ==
[ ] Customify – Version 0.1.0
[ ] OnePress – Version 2.0.8
[a] Zincorpora??es – Version 1.0.0
3 themes present.

== Listed Plugins ==
[a] Anywhere Elementor – Version 1.0
[a] Categories Images – Version 2.5.4
[a] Check Email – Version 0.5.5
[a] CMB2 – Version 2.4.2
[a] CMB2 Admin Extension – Version 0.2.3
[a] CMB2 Tabs – Version 1.0.6
[a] Contact Form 7 – Version 5.0.2
[a] Debug Info – Version 1.3.6
[a] Debug Objects – Version 2.5.0
[a] Diagnostic Glance – Version 0.9.2
[a] Easy WP SMTP – Version 1.3.6
[a] Elementor – Version 2.0.14
[a] Insert PHP Code Snippet – Version 1.2.4
[a] Open Graph – Version 1.8.1
[a] Press Elements – Widgets for Elementor – Version 1.7.2
[a] Query Monitor – Version 3.0.1
[a] Search & Filter – Version 1.2.9
[a] Smush – Version 2.7.9.1
[a] Theme Check – Version 20160523.1
[a] Theme Editor – Version 1.6
[a] Twitter Cards Meta – Version 2.9.0
[a] UpdraftPlus – Backup/Restore – Version 1.14.11
[a] WordPress Importer – Version 0.6.4
[a] WP Downgrade | Specific Core Version – Version 1.1.4
[a] WP Rollback – Version 1.5
25 active plugins out of 25 present

== WordPress Config ==
Permalink Structure: /%year%/%monthnum%/%day%/%postname%/
Category Base: undefined
Tag Base: undefined
WP Max Memory Limit: 256M
WP Memory Limit: 256M
WP Max Upload Size: 64M
WP Cache: off
WP Debug: off
WP Debug Log: off
WP Debug Display: on
Display Errors: off
Log Errors: on
Error Log Path: error_log
Concatenate Scripts: default*
Allow Multisite: default*
Disable Auto Updates: default*
Enable Core Updates: default*
Disallow File Edit: default*
Disallow File Mods: default*
*default – not explicitly set in wp-config.php,
so wp defaults apply.

== Hosting and System Config ==
Server: Apache
PHP Version: 7.1.16
MySQL Database Version: 5.6.39
PHP Memory Limit: 256M
PHP Max Upload Size: 64M
PHP Post Max Size: 64M
PHP SAPI: cgi-fcgi.

== PHP Extensions [ 35 Enabled ] ==
cgi-fcgi, Core, ctype, date,
dom, filter, ftp, hash,
json, libxml, mysqli, mysqlnd,
openssl, pcntl, pcre, PDO,
pdo_mysql, pdo_sqlite, Phar, posix,
readline, Reflection, session, SimpleXML,
SPL, sqlite3, standard, tokenizer,
wddx, xml, xmlreader, xmlwriter,
xsl, zip, zlib

== Apache Module List Unavailable ==
You’re running PHP as cgi-fcgi.

== General Site Statistics ==
Administrators: 1
Authors: 3
Nones: 0
Total Users: 4
Published Pages: 6
Draft Pages: 0
Published Posts: 0
Draft Posts: 1
Comments in Moderation: 0
Comments Approved: 0
Comments Spam: 0
Comments Trash: 0
All Comments: 0
Images: 234
Other Media: 0
All Media: 234

The page I need help with: [log in to see the link]