@Crunchie1978 check the speed to the hub by running the Service Checker in the My Sky app which if you click on the Broadband link will show the recent speed history and the guaranteed speed for your line. If the speed to the hub is below the guarantee then the app should offer further help.
If however that is all as it should be the problem is the WiFi signal in your home which isnt guaranteed by Sky. You can buy an add-on from Sky which does get you a wifi guarantee see https://www.sky.com/help/articles/sky-wifi-max
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
