Hello,
my bet is on ooredoo.
if it is the case we won't know as the forum focuses on mostly french service providers. They all have some sort of specific configuration to hinder clients for connecting anything too easily on their network.
also more and more service providers now provide IP in CGNAT ranges. A public IPv4 address is an option, when it is an option. Moving to IPv6 is the way to go, also if the service provider provides IPv6 connectivity.