Here at SecureW2, where we help users connect to secure Wi-Fi all over the world, we’ve been seeing an interesting issue with Apple’s iOS 9.x version. Specifically, devices running iOS 9+ will not connect to an SSID after a password change. This issue affects both Pre-Shared keys and credential based authentication mechanisms, leaving many end users frustrated because they suddenly were unable to connect to the network that was previously working just fine.…

Source: iOS 9.x Wi-Fi Connectivity Issue with EAP-TTLS and EAP-PEAP: Explained – SecureW2