Hello,
This problem should be solved in version 2.1.3+
You can check this
TOPIC: HELP!!! Nothing but Issues!!!
But I consulted problem with other developers and you can try this modification:
Open file administrator/components/com_booking/helpers/config.php
There is this row:
require_once(JPATH_ROOT.DS.'components'.DS.'com_booking'.DS.'assets'.DS.'libraries'.DS.'mobile_detect'.DS.'Mobile_Detect.php');
Modify it to:
if (!class_exists('Mobile_Detect'))
require_once(JPATH_ROOT.DS.'components'.DS.'com_booking'.DS.'assets'.DS.'libraries'.DS.'mobile_detect'.DS.'Mobile_Detect.php');
Let us know if it helps.