Openpay LIBRARY

It's hard to be sure, as there are two questions here, but I believe that with CI4 you are better off using the namespaces rather than the older method of directly loading the php files with the require_once function.

The simplest way, is to insert a USE statement at the top of the file, with the path to the library file, such as:

PHP Code:

use path/to/library 


If you are using something like VS Code, then you can have the system insert that line for you when you find an unknown class.

I am not using OpenPay, so cannot give you direct help, but that should point you in the right direction.