Something weird going on with Wifi settings

One of my Windows 10 laptops has suddenly decided it won't connect to Wifi, but it's not quite as simple as that. I have two networks at home. Other PC's and devices in the house are connected to both networks. My Dell E7440 has decided it does not want to conect to either network via Wifi using a password.

Every time I enter the password for either network i get a "cannot connect" message. The passwords have not changed and all other devices can connect. I can connect to the internet through both routers via LAN cable. I thought maybe it was my wifi adapter that was at fault however this is not the case. Through one of my network service providers I have hotspot capabilities. I can actually connect to that router as a hotspot so I know the wifi adapter is working.

I've tried turning the laptop off an on. I've turned the wifi off and on. I've been through the troubleshooter which identified no problems. I've checked the drivers and I have the latest installed.

Any ideas because I'm stumped?

Hi there. Just downloaded. The signal's not brilliant but it's not that bad either. I have sat next to both routers and tried.