Unlocking a locked Router settings by Airtel XStream Fiber Broadband

While rooting and unlocking might work, it might as well break a few things.

I will just suggest you an alternate option.

To my knowledge Airtel offers Bridge Mode on one of the LAN ports of their ONT router. Just that you have to get it enabled with the help of their NOC team from backend. Their immediate support is likely to reject your request or will have no knowledge what is Bridge Mode!! You have to discuss with a technician to allow you to connect to NOC or you have to write to net@airtel.com

Once your ISP ONT router is in Bridge mode, now connect your own fully functional Ethernet router to it.

LAN cable goes from Bridged LAN port of ISP ONT to WAN port of your router. Now your router is front ending WAN internet and now set it up the way you like. In router mode, you will have full control over all the features and options.

Note – This is not to be confused with usual Access Point Mode.

The NOKIA ONT router from Airtel is already as router(route mode),but settings are greyed out.
I want to modify the settings of the Airtel Router AOT4221NK,IF THAT IS POSSIBLE.

What I have suggested is an alternate way to get full control over various settings that you intend to control, just in case you do not find a way to root the ISP provided ONT.
In Brigde mode, ONT+Router = Only ONT i.e. at a simplistic level pass optical to Ethernet. In Bridge mode routing functions are not in effect.
That's what I tested with airtel when I was using their internet and now with Tata.

@whitestar_999 , my Friend, any thoughts?

Well ditched Airtel XStream and back to Alliance BB again.