Port Forwarding Blocked on Airtel in Bangalore

[5zan]

I have GX 2122A router from Airtel and i am using it in bridge mode.(PPPOE) Unfortunately I am unable to do port forwarding at all, even after opening a port on my Asus router it does not work. Is there anything that I'm missing? There was no such issue with Hathway who was my previous ISP.

 

[Lolita_Magnum]

What is the WAN IP you are receiving on your router?

 

[rohitks]

A few things I can comment
1. Airtel is moving to CGNAT where they will no longer offer free public (routable) IP to their users. You may be behind CGNAT (That's why I suppose @Lolita_Magnum is asking you to confirm in above post?
2. When you put ONT in bridge, ideally all WAN dependent features + DHCP, WiFi should shut down but that's older way. Now both run concurrently on both routers. So if you have any firewall enabled on GX it might be taking precedence. So if you get Public IP make sure that firewall, port forwarding rules, etc are all disabled on GX and they should only be configured on Asus
3. If you remove bridge and directly connect your device to GX, does port forwarding work?
4. To verify port forwarding is working, you must have a service listening on that port, if not port warding works but you don't feel it