“Fatal Error: ‘Uncaught Error: Class ‘Culqi\\Culqi’ not found in

I get a module for culqi payment method and after using in magento 2

I get error which are below

"Fatal Error: 'Uncaught Error: Class 'Culqi\Culqi' not found in  

Code This is place where i am getting exception:

    $  objCulqi = new \Culqi\Culqi(['api_key' => $  this->_privateKey]);     $  charge = $  objCulqi->Charges->create($  requestData); 

IS Class i have to create for this

Please if someone help

Thanks