My Scenario: I was able to connect with my home Wi-Fi without any problem, but after a minute or two the internet stopped working. I wasn't able to access the internet nor connect to my router's admin panel (via my iPhone although the Wi-Fi signals were strong). And after disconnecting and reconnecting to my Wi-Fi, everything was working a-okay. Only my iPhone 7 Plus and other iOS devices in my house were facing this issue and no other device like laptop and android phones were affected by this weird problem. THE FIX: From setting manual DNS to resetting Wi-Fi router and my device, I tried everything but nothing worked. What worked was CHANGING MY Wi-Fi ROUTER! Although I wasn't facing any connectivity issues on my laptop or android phone whatsoever, somehow my router wasn't properly working with my iPhone 7 Plus and other iOS devices of my friends.