Updated to IOS 11.2.6 and my wifi will not work anymore

Hi

i am a uni student and use my phone for a lot of work regarding my degree, but when i updated my phone to ios 11.2.6 my phone WiFi has died completely. I cant use it for anything now.

i can connect to various WiFi connections/ cellular hot-spots, but after a few seconds the WiFi icon at the top of the screen disappears and i lose all internet connection. i know it works to start with as ill get a flood of notifications and emails and then dead. if i go into settings and WiFi it says i'm connected and that there is internet access (which i know there is as my flat mates phones and computers all connect fine, the only difference is i'm on ios 11.2.6). when trying to connect if i go out to the main settings page while trying to connect the VPN on/off slider is going spastic flicking between on and off without me touching a thing.

i have tried everything from soft reset to deleting the networks and re-adding them and even reinstalling ios 11.2.6 through iTunes on recovery mode.

as you can see below i am connected to the internet yet no wifi icon, when i first connect ( no more than 5 seconds) the wifi icon is present while it is there everything works fine and i get the various notifications.

Any help would be massively appreciated i desperately need this fixed soon for university.

thank you in advance for your help

- Jared