@PaigeRhianne unless the fibre pigtail has become disconnected you can't fix it. It's down to Openreach as the ONT is not getting an optical signal. Call Sky and report the issue.
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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
