Why doesn't CSalePaySystemAction::GetParamValue work in helper.php?

Question

PHP

Hello. I am embedding the payment system in the Bitrix Framework. After setting up, I go to the payment page and it gives an error.

The key 'APPROVE_METHOD' was not found in the GLOBALS[SALE_CORRESPONDENCE] array and no default value was defined.

The key "APPROVE_METHOD" is declared in

.description.php

The D7 kernel documentation says that calling data with

CSalePaySystemAction::GetParamValue

only available in file

payment.php

but the payment system is written so that helpers work first.

helper.php

in which there is an appeal to the data of the payment system

CSalePaySystemAction::GetParamValue("APPROVE_METHOD");

which is why the error occurs.
Question: Is it possible to call values ​​in helper.php or change them somehow? File connection

.description.php

does not solve this problem.

Answer 1

and in a helper you connect classes through namespaces?
Most probably not

Answer 2

Interestingly, CSalePaySystemAction::GetParamValue also returned empty in payment.php. But there was $arResult, from where I got everything I needed.
And on another site there is no $arResult, but CSalePaySystemAction::GetParamValue works. Wonderful are your Bitrix))