authorizenet not working in live server : I am using this code to create customer profile

http://developer.authorize.net/api/reference/index.html#customer-profiles-create-customer-profile

this is working fine locally but not working in live server. Showing 500 server error when execute the line no 58. (see sample code in above link)

My php version 5.4+ in server and met all requirement mentioned in https://github.com/AuthorizeNet/sdk-php

even all dependent library available in server which is required for this SDK

** working on sandbox