PUN Connection issue in Sudan

Hi,

I have a game which is using Photon Unity Networking (PUN) and its connection is working fine in most of the countries except in Sudan. Recently I got many mails from Country => Sudan and their complain is, they have issue with PUN, they never connected and unable to play online multiplayer.

When I asked, "do you play on wifi or mobile network?", they said, they are using mobile network (Sudani) and (zain).

This is major issue. I have 30% users from Sudan.

Please let me know what is exact issue?

-Vikash