@Eee if the hub is connected to the exchange (see https://www.sky.com/help/articles/hub-lights-explained-start) but devices look to be connected butno data flows power down the hub for an hour as that can clear the fault that causes that issue.
If however your devices simply cannot be connected to the hub and wont accept the wifi password reset a black hub by pressing and holding in the reset pin until the power led flashes or on a white hub hold down the wps button for 20 seconds until the led stats flashing green. If that works consider how someone changed the wifi password without you knowing. This can only be done locally it cannot be done unless the device used is on the network
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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
