GoKawiilFixing double NAT: bridge mode vs access point mode for home routers
When a home network has both an ISP-supplied gateway and a personal router or mesh system, leaving both in default settings can create double NAT, since the ISP gateway keeps routing traffic even when connected to another router. The fix is to either put the ISP gateway into bridge mode so it stops routing, or switch the personal router into access point mode so it only extends Wi-Fi while the gateway keeps routing.