Need to setup dsl connection on pc having already another connection

Dear friends in my office we have a wireless networking via a wireless router which is also connected to DSL modem and we access internet, i want to have separate DSL connection in my office which should directly connect to my pc.

I bought another connection but when i used to connect my separate DSL i gt disconnected from office network i cannot access other pcs which are on network.plzz help me out how to solve the conflict.
router ip is 192.168.1.1
network DSL modem ip is 192.168.1.1
network pcs have ip from 192.168.1.10 to 19

my separate DSL modem have also ip of 192.168.1.1.