Netgear WN3000RPv3 WiFi extender not detecting only base router SSID

I recently upgraded my base router to Nokia 5G router. Initially it worked well with my extender but now my extender does not detect only that particular SSID. It shows all Wifi SSIDs, even my Mobile HotSpot SSID but not my base router's SSID.
I have even tried keeping the Wifi extender next to my Base router, even then it won't detect.

My laptop and other devices can easily detect base router SSID and connect to it.

Have tried Factory reset on both the Base Router & Wifi Extender. Any suggestions?