Facebook Messenger End to End Encryption not sending messages behind Sophos XG Firewall

Does anyone experienced the same thing? Messenger app chats with End to End Encryption enabled cannot send messages behind Sophos XG Firewall. There's also a lot of ISAKMP VPN hits in the traffic insights recently. I'm also thinking my XG instance is blocking Signal protocol. Accessing the messenger via browser is not affected, only the messenger android app. But before I tinker around the settings, i guess it will be better to consult here.



Edited TAGs
[edited by: Erick Jan at 4:42 AM (GMT -7) on 16 Apr 2024]