pls help : Not Able to edit in Action section in Settings

pls help

I am getting this msg: when i try to edit in Action section in System::Settings

Fatal error: Class 'Controllersettingsetting' not found in /home/zdel/public_html/vqmod/vqcache/vq2-system_engine_front.php on line 74

Using OpenCart
Version 1.5.6.4 -

Thanks for your time
Regards
Vijay

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