Integration With Fawry Pay

Dears,
I have issue to integrate with a payment gateway “Fawry Pay”

the integration works fine on their plugin i can send them the order but the callback is not working perfectly as per my understanding i just should provide them with callback url

then they asked to deploy this on woocommerce
https://developer.fawrystaging.com/docs/plugins/payment-notifications/server-notification-v1

i actually dont know what they mean

they send this as a prove of the issue from WC side

[10/4/20 13:56:44:291 SAST] 000003c4 MerchantInteg I MerchantIntegrationService sendHTTPRequest Http respons code = 403 for merchant = 1000004564 request payload {“requestId”:”f5da095c512a475cbd0857ac4700226b”,”fawryRefNumber”:”973038095″,”merchantRefNumber”:”28038″,”customerMobile”:”+201147888864″,”customerMail”:”admin@kpi-academy.com”,”paymentAmount”:3.0,”orderAmount”:1.0,”fawryFees”:2.0,”orderStatus”:”PAID”,”paymentMethod”:”CARD”,”paymentTime”:1601812603435,”authNumber”:”502020″,”messageSignature”:”4f98c9fe2711db96b5b49b142c5bec21d23490ff5309543d6dc94e22e57fd624″,”paymentRefrenceNumber”:”1469319268″,”orderExpiryDate”:1601813125213,”orderItems”:[{“itemCode”:”28038″,”price”:1.0,”quantity”:1}]}

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