hot to add new server

[ukdomainers]

when i try add a server

i get ]

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exception 'Whoops\Exception\ErrorException' with message 'require_once(): Failed opening required 'lib/senitor/vendor/autoload.php' (include_path='.:/opt/alt/php56/usr/share/pear:/opt/alt/php56/usr/share/php')' in /home/ukdomain/public_html/whmcs/modules/servers/sentora/sentora.php:115
Stack trace:
#0 /home/ukdomain/public_html/whmcs/vendor/whmcs/whmcs-foundation/lib/Utility/Error/Run.php(0): WHMCS\Utility\Error\Run->handleError(64, 'require_once():...', '/home/ukdomain/...', 115)
#1 [internal function]: WHMCS\Utility\Error\Run->handleShutdown()
#2 {main}