Slow connection across all devices

[Sky-Gemma]

I'm a new customer and have gigafast broadband. I've ran tests and the app says that all is good. However, all devices are running incredibly slow when connected to WiFi. Eg- I'm using my mobile and it's taking between 5-10 seconds to respond to each click. My tv couldn't even load Disney or Prime and took minutes to load Netflix. 
What could be the problem and how can I resolve? 
thanks 

[J_ham]

Hi there @Sky-Gemma , I’ve escalated your post to our Community Messaging team who will invite you to a private chat shortly and help you with this. 

Just look out for the colourful bubble to start the conversation. Please be aware conversations automatically close if there is no response within 48 hours.

Here's more information on how Community Messaging works - https://helpforum.sky.com/t5/Did-you-know/Escalating-a-post-to-a-Sky-expert/ba-p/3711147#M141