How to Use WHMCS license :

Download License.php file and license key for asking Hosttiller.com support whatsapp :+8801911336699

and replace it with YOUR-WHMCS-PATH/vendor/whmcs/whmcs-foundation/lib/License.php

How to Update the whmcs :
1: Update with the Automatic Updater

2: Updating WHMCS Manually in the Browser

Known Errors Solution

1: License error page after upgrade WHMCS : if You see license error page after update or upgrade of whmcs please follow below solution:

Download License.php file from client area of Hosttiller.com or Contact with hosttiller.com

and replace it with YOUR-WHMCS-PATH/vendor/whmcs/whmcs-foundation/lib/License.php

2: How to Upgrade PHP for WHMCS upgrade Using cPanel MultiPHP

Follow the link : https://help.whmcs.com/m/updating/l/1309170-how-to-upgrade-php-for-whmcs-using-cpanel-multiphp