Below content is similar for AX2 as well as Atomic
When testing MIR cards in an APEXX/Ingenico pre-production (sandbox) environment, transactions keep getting declined.
The payment request requires specific values for authorisations to succeed.
Ensure that the country attribute in the billing address block is set to “RU”
Ensure that the test card number in the request is valid for the desired result. please refer to this list of MIR test cards. An example of a card number that will authorise successfully is 2202207558945880
Refer to attached sample request