@Rosey13 WiFi in blocks of flats can be difficult especially if the internal walls are made of concrete. However I would expect the signal to be strong enough to connect to but given in most flats you are surrounded by neighbours each with their own wifi networks all compteting fir the limited number of WiFi channels so interference is almost a given which makes streaming video and playing games a pain.
Check your hub is in the best possible position which is on a surface out in the open. After that you are into needing wifi extenders whuch Sky can supply if you buy their Wifi Max bundle 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
