You can’t access to the customer Lan site from your ISP site (192.168.0.1/24 )on basic routing .If you trying to access 192.168.40.1 you should be in customer Lan site . you are not wrong .
yeah definitely i can access 192.168.40.1 from user that connected to that wifi…
but my question is can i access it from my LAN (192.168.0.1/24) ?? because range between AP is so far, theres no way i must come to their every time i want to access AP setup.
I mean if your PC IP is 192.168.0.XX network use this IP for access your AP 192.168.0.90 ( this is your AP WAN IP right ? ) .
If your PC IP is 192.168.40.XX network user this IP for access your AP 192.168.40.1.
in order to configure your AP via its WAN IP (192.16.0.90) you most likely must enable remote management on the AP.
According to the manual [1] (chapter 4.10.4) you need to go to Security → Remote Management and fill in 192.168.0.90 in the Remote Management IP Address field.
After you have done that you should be able to connect to http://192.168.0.90 from your PC (192.168.0.3).