Changing NAT type from 3 to 2 question

[marskeiko123]

I am not a computer expert so my current home internet setup was actually done by paying some professional IT guy to help do it. As the range of one router is not enough to cover my house, there is a main router in our living room and it connects to the ISP modem and all the routers that are in the other rooms. So if I want to use wi fi I just connect to the router in my room. So now my PS4 is also connected to this router and the connection status says it is currently NAT type 3. I have tried searching for hours online to change the setup of my linksys WRT120N but nothing worked. However, when I removed the router and plugged my ps4 directly to the wall (using LAN cable) instead, the NAT type is now 2. Does anyone know why is that and how to fix it? Do I need to buy a new router? Thanks in advance

 

[USAFRet]

there is a main router in our living room and it connects to all the routers that are in the other rooms

To me, this means your "professional IT guy" is an idiot.
In a residential situation, there is rarely a need for more than one 'router'.

Dedicated access points, maybe (given a large house).
More routers....almost certainly not.

 

[marskeiko123]

Basically I cannot connect to the main router from my room due to range but the main router is hooked up to the ISP modem. Every time the modem or the main router is down, I will lose internet connection even if the router in my room is fine.