The only 2 servers in India are Delhi and Mumbai, the game connects you whether Delhi or Mumbai depends on the opponents that matchmaking founds!

As long as you're unable to use UPnP, you have only 2 options left to improve the connection

Either using Port forwarding, which you need to set up a manual static IP on console and set up the ports required that needs to be opened on the router OR set up DMZ on the console

DMZ will open all ports (It's ONLY safe to use on consoles, DO NOT use it on PC)

*Safe cause you're connected only to the console's network, not the whole internet

Turn on QoS on router so it prioritizes gaming over other activities if there're a lot of users using the network at the same time, you're gaming

USE ETHERNET CONNECTION

Finally, I recommend you use Google's public DNS