mtls verify always failed

[Skrill]

I have setup mtls on aws load balancer, but when verified certificate from shopify it always failed.
i have created my own certificate to test and it works. but when using shopify certificate it always failed.

i use chain certificate from this documentation https://shopify.dev/docs/apps/build/payments/considerations
i copy the certificate to file ca.pem and added it on trust store.

what should i do?

what actually shopfy send to the app? is it something like this?
curl -i -H "Content-type: application/json" --key shopify.key --cert shopify.crt {my shopify paymentapp extension - payment session url}

Thank you.