I'm currently trying to get a secondary HG659b router I requested from Spark setup as an access point to extend the Wi-Fi range as well as allow my PC to still be hooked up via ethernet however, I'm having no luck and this is why:

• When changing the IP address as instructed on Spark's official guide to 192.164.3.x instead of 192.168.1.x I lose access to the router settings.
• I'm unable to change the subnet from 255.255.255.0 to 255.255.0.0 as suggested by online advice I've found. (Subnet does seem to change to 255.255.0.0 when I change the IP but then I get a blank Default Gateway)

I've currently changed the following settings:

• DHCP Server has been disabled on the AP.
• NAT has been disabled on the AP.
• The SSID has been changed on the AP for recognition purposes.
• IP address to 192.168.3.254 (Doesn't work as mentioned above)

I tried to plug the router in via LAN1 to LAN1 from the main router to the AP router despite losing access to the AP to see if perhaps it would work anyway but that didn't do anything either.

I'm stumped and have no idea how to resolve this so I'm hoping someone knows what the potential issue is and can give me a hand. Really appreciate any help!