@HarryH65 assuming the "repeaters" are the matched pod extenders supplied by Sky it sounds like the alarm unit is out of useful range. If the unit is in the home you could try moving one of the pods to a better location but remember the pods need a good backhaul connection to the hub. Sky will provide a third pod as part of the WiFi Max bundle but will probably want to send out an engineer first.
If the unit is outside on a wall that gets more complex as the guarantees only apply to devices in the home.
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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
