@Eugene6 the Openreach unit is called an ONT and the red light means it is not receiving an optical signal which means there is an issue either with the fibre line or the equipment in the exchange that generates the signal. Effectively there is little you can do yourself except checking the pigtail cable is plugged in under the ONT.
Quickly run the service checker in the My Sky app using a mibile connection as thst shoulld tell you if Sky already are aware of an issue affecting your line. If they aren't call them so they can get Openreach tonrepair the fault.
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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
