I install wishlist module in our project.When i call any api of this module it showing some error: <br /> <b>Fatal error</b>: Uncaught Error: Cannot instantiate interface Ipragmatech\Ipwishlist\Api\WishlistManagementInterface in /opt/lampp/htdocs/foxministry_v2/vendor/magento/framework/ObjectManager/Factory/Dynamic/Developer.php:73 Stack trace: #0 /opt/lampp/htdocs/foxministry_v2/vendor/magento/framework/ObjectManager/ObjectManager.php(71): Magento\Framework\ObjectManager\Factory\Dynamic\Developer->create('Ipragmatech\\Ipw...') #1 /opt/lampp/htdocs/foxministry_v2/vendor/magento/module-webapi/Controller/Rest.php(305): Magento\Framework\ObjectManager\ObjectManager->get('Ipragmatech\\Ipw...') #2 /opt/lampp/htdocs/foxministry_v2/vendor/magento/module-webapi/Controller/Rest.php(216): Magento\Webapi\Controller\Rest->processApiRequest() #3 /opt/lampp/htdocs/foxministry_v2/var/generation/Magento/Webapi/Controller/Rest/Interceptor.php(37): Magento\Webapi\Controller\Rest->dispatch(Object(Magento\Framework\App\Request\Http)) #4 /opt/lampp/htdocs/foxministry_v2/vendor/magento/framework/App/Http.php(135): Magento\Webapi\Controller\Rest\Intercept in <b>/opt/lampp/htdocs/foxministry_v2/vendor/magento/framework/ObjectManager/Factory/Dynamic/Developer.php</b> on line <b>73</b><br /> {"messages":{"error":[{"code":500,"message":"Server internal error. See details in report api\/946085665948"}]}} Anybody help me for removing this error.