@Chinnasamy 

Yes

  @ManojAgrawal https://community.tp-link.com/en/home/forum/topic/594490

Is your local exchange run GPON ONT in the exchange? I believe BSNL runs EPON in all regions except Kerala. 

In the Advance settings, Internet, See if you are able to change the operating mode from GPON to EPON in XPON settings. 

  @ManojAgrawal Check with a regional technician who does the router configuration for a new connection. 

Double-check is that GPON if yes, they have to provide login credentials for GPON to connect with incase of EPON you don't need credentials to connect to ONT but making a PPP connection needs a username and password. 

  @ManojAgrawal  Looks like you are using an older version of the router (Understand based ion the settings you mentioned.) 

There is 2 version of Router devices TPLink sells to India.  Unfortunately the model number is same XC220-G3v

1) https://www.tp-link.com/in/service-provider/gpon/xc220-g3v/ - This is new version of XPON (GPON/EPON) router launched recently (Nov/Dec 2022) which we can use to connect to either GPON or EPON ONT. This router will give you advance option to switch the operating mode between EPON/GPON. 

2) This is older version for TPLINk router which supports only GPON. 

I am assuming you are having 2nd one and trying to connect to BSNL which will not work. 
 

Can you please verify both router images and see which one you have? 

  @Chinnasamy 

  @ManojAgrawal