Problems with WHMCS pages: Meta Tag issue with search engine

[hostmonitor]

Pls help me correct these issues, SEO keep saying i have Duplicate meta description tags and Duplicate title tags

 

It shows me the below pages as pages that have the issues, how can i fix these issues?

 

example.com/knowledgebase.php
example.com/knowledgebase/1/How-to-Install-a-ScriptorSoftware-Using-Softaculous.html
example.com/knowledgebase/1/Softaculous
example.com/knowledgebase/10/How-To-Create-Master-Reseller-With-WHMPHP.html

example.com/cart.php
example.com/cart.php?a=add&domain=register
example.com/cart.php?a=add&domain=register&currency=1
example.com/cart.php?a=add&domain=transfer
example.com/cart.php?a=add&domain=transfer&currency=3
example.com/cart.php?a=add&pid=1
example.com/cart.php?a=add&pid=10

example.com/announcements.php
example.com/announcements.php?view=2015-04
example.com/announcements.php?view=older
example.com/announcements/2/New-Server-Launched.html

example.com/domainchecker.php
example.com/domainchecker.php?currency=1
example.com/domainchecker.php?currency=3
example.com/domainchecker.php?search=bulk
example.com/domainchecker.php?search=bulk&currency=1
example.com/domainchecker.php?search=bulkregister

example.com/downloads
example.com/downloads.php

example.com/submitticket.php
example.com/submitticket.php?step=2&deptid=2

 

AND MANY MORE

 

ANY IDEA FOR CORRECTION, THANKS