500 error during the payment - checkout psp

[Veranicka]

Hi,  

I activated the checkout psp and I’m getting 500 http error when I validate credit card (screenshot below)

I don’t have any information what happen in the server or the issue log,

please let me know the error and how to debug ?

-Details:

website: v-nationstore.com
environment: Test

psp environment: test

thanks in advance.