@ErikaChan if you want relevant help you are going to have to give more details. I assume by lagging you mean hight latency when gaming. Causesccan be down to poor WiFi in your home which is very common and is why Ethernet cables are highly recommended for networking gaming devices. Second issue can be load on the Sky hubs as routers can struggle when there are mutiple users all active. Next is simply server overload or poor routing. Lastly in probability is the line in the main Sky's and Openreach's networks are reasonably fast but issues can happen.
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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
