@MartP check the Service Checker in the My Sky app or website as Sky checks thecspeed to your hub daily - clicking through from the last result shows you the last 21 days results and the guaranteed speed to your hub. If thecspedds havecdropped below the guarantee for 3 days the app should offer further help or call Sky.
If the speed tests look OK it is likely the issue is with the wifi signal in your home. This can be affected by interference or simply something has been moved. Consider what if anything could be the issue in your home. Interference can be from neighbours' networks or from your own electrical equipment especially if it is close to the hub. In the end you may need a wifi extender or similar.
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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
