1) Newer mobile phones support MAC address randomization per default. There should be 3 settings for your SSID: - use per-connection randomized MAC - use per-network randomized MAC - use device MAC Try 2nd or 3rd, it may help. 2) It could also be related to using "private DNS mode" in the "Network & Internet" settings menu. Try switching it off. 3) Can you access your routers' internal IP in a Browser on your phone, i.e. http://192.168.0.1? If yes, it looks like a DNS issue.