To receive callback responses from FONDY following server IP addresses must be allowed in the merchant site firewall:
54.154.216.60
The callback is considered to be processed successfully by the merchant if HTTP 200 OK status returned.
Otherwise FONDY will repeat callback attempts with such time intervals: 2, 60, 300, 600, 3600, 86400 seconds.
Request header user-agent will contain following value: Mozilla/5.0 (X11; Linux x86_64; Twisted) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.108 Safari/537.36