Hey there. I've recently changed phones as my old one is cracked and I'm lending a phone from my boyfriend. The phone is a huawei P8lite, its been working fine with the wifi since I changed it but when I got home tonight it wouldn't connect and kept saying 'denied acess to network. Connection failed.' Which doesn't make sense because this morning it was connected and both my mom and brothers phones connected and my brother has the excact same phone as the one I'm lending. So I'm not sure whats going on. P.S we don't have a landline that our router is connected to, its fiber and the router says nokia on it, not sure what type of router it is.
That is a message you get when the info for the connection has changed. Like a changed password or even the modem/router settings were changed to block that device (which can be done).
I would ask if anyone changed any of the settings on the modem/router. That is the best place to start.
Should that not do it, and no password change, then try 'forgetting' the information for that connection on the phone. Restart (turn it off and back on) the phone and then try reconnecting to that WiFi.