Wi-Fi can be mysterious to get functioning on a smartphone sometimes. One of my computer repair clients was frustrated with their iPhone 6 last weekend. Their data plan was being gobbled up so they disabled their cellular mobile data under settings. They assumed their home Wi-Fi network was going to take over but it didn’t. Now they couldn’t browse the internet or get their email. They also wanted to do a iPhone backup which sucks up a lot of data over the cellular network. It’s smarter to do it over Wi-Fi.
They assumed the iPhone was connected to their WiFi network and it was. It was not Ietting them browse the internet although It had worked in the past. Using my smartphones, I verified they could connect to the home network and they both could. Now I knew the problem was with the iPhone and not their Wi-Fi router. I next checked under settings- Wi-Fi and saw the network name. All settings were checked like security and password and they looked correct. I disconnected and reconnected to it and still no internet.
As a last attempt, I deleted the WiFi network connection under settings and then let the iPhone reattach. The network was configured and it began working. Now and my client can perform their iPhone backup. I double-checked that the mobile network data was still disabled and it was. Sometimes, you have to remove and reinstall to solve your problem!