Issue with creating product bundles

[TrippleEx]

We create a Bundle with two Products with the Type: Others:



I f i try to open the the Product Bundle Link like: https://mydomains.com/cart.php?a=add&bid=6

I get as result a 404 Error, but the First istem is added to the cart:


With refreshing the Browser with F5, both items will be show in the cart:

The Appache Error Logs in cPanel show me:

[Sat Jan 30 18:25:38.331291 2021] [:error] [pid 17594] [client xxx.xxx.78.10:12809] client denied by server configuration: /home/myaccount/public_html/cart.php
[Sat Jan 30 18:21:24.423402 2021] [:error] [pid 21287] [client xxx.xxx.78.10:13107] client denied by server configuration: /home/myaccount/public_html/cart.php
[Sat Jan 30 18:20:53.696031 2021] [:error] [pid 21483] [client xxx.xxx.78.10:12810] client denied by server configuration: /home/myaccount/public_html/cart.php

The content of our .htaccess is:

### BEGIN - WHMCS managed rules - DO NOT EDIT BETWEEN WHMCS MARKERS ###
<IfModule mod_rewrite.c>
RewriteEngine on

# RewriteBase is set to "/" so rules do not need updating if the
# installation directory is relocated.  It is imperative that
# there is also a RewriteCond rule later that can effectively get
# the actual value by comparison against the request URI.
#
# If there are _any_ other RewriteBase directives in this file,
# the last entry will take precedence!
RewriteBase /

# Redirect directories to an address with slash
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^(.+[^/])$  $1/ [R]

# Send all remaining (routable paths) through index.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
# Determine and use the actual base
RewriteCond $0#%{REQUEST_URI} ([^#]*)#(.*)\1$
RewriteRule ^.*$ %2index.php [QSA,L]
</IfModule>
### END - WHMCS managed rules - DO NOT EDIT BETWEEN WHMCS MARKERS ###

# php -- BEGIN cPanel-generated handler, do not edit
# Set the “ea-php73” package as the default “PHP” programming language.
<IfModule mime_module>
  AddHandler application/x-httpd-ea-php73 .php .php7 .phtml
</IfModule>
# php -- END cPanel-generated handler, do not edit

We have try it with deactivating all Modules Addons, Hooks und try it with Six Template and Default Orderform.

But we allways get this 404 Error.

I have also alread open a Support Ticket, but Level 1 Support guys was not able to solve it, they redirect it to their Level 2 Support colleagues.

Anyone had the the same issue or similar one, maybe someone can give me recommendations as to what the problem is actually or possibly how I can fix this problem.

Warm regards

Edited January 30, 2021 by TrippleEx

[TrippleEx]

The issue has been solved, it was releated by the Apache Module: Evasive (DDoS Protection Module).