Custom Class not working on server

I am using phalcon in one of the my project and i'm using some custom classes for whole application its just like a plugin the issue is the project is working on our local and stagging server but when I upload this to client server i gout class not found error I have registered the classes into loader but that is not working only client servers ther we have installed the phalcon successfully but getting error into error logs.

Please help me for this issue.

The given information is not complete.

please post your loader initialization and error code / exception that you got.