Internet not connecting since fibre upgrade

[SarahHatesTech]

We had superfast fibre installed on Monday. Since then, internet has been slow or dropping on multiple devices. XBox upstairs used to work perfectly but now really laggy. Chrome book not connecting to internet, despite showing strong connection. Today, TV is also not connecting to internet. It says it's connecting to broadband router but there is no connection to internet. Have tried all the suggested resets and reboots. Any ideas?? 

[jamesn123]

@SarahHatesTech 

What did you have before?

[SarahHatesTech]

Standard Sky Broadband - fast/superfast but not fibre. 
I've managed to connect the TV by changing the HP address, etc and it seems ok at the moment - everything working as it should. 
Tried doing the same to the chrome book - it's showing as connected now but won't actually connect to anything. 
My phone was ok earlier but is now so slow I'm using 4G instead. 

[jamesn123]

@SarahHatesTech 

Please post your router stats

https://helpforum.sky.com/t5/Broadband/How-to-find-your-Sky-Broadband-router-stats/td-p/2855717/jump...

You may also need to disable Sky Shield

https://www.sky.com/myaccount/bb-and-talk/broadband-shield