Firstly, please check for the permission at the server or web hosting where your files are placed. You should have the necessary permission like read, write, and execute.
Secondly, the php_curl module should be installed and enabled at your server or web hosting. You can check for a php_curl module with the help of phpinfo function. Once you browse the phpinfo.php page, you will able to find php_curl as enabled.
If you are still facing any issue integrating PHP Sample code, please share the PHP Sample code you are using with the exact error or exception.
You can always contact RChilli Support via creating a ticket at RChilli HelpDesk or simply by sending an email at firstname.lastname@example.org. The support team will assist you further regarding your account information. We will check it and provide you the solution accordingly.