Extension kit not calling heat for SRT
I've had a starter kit for a while, with extension kit, bridge and smart room thermostat which looks after heating and hot water in the traditional way.
Just bought some smart radiator valves which caused a lot of grief with no heating! the existing smart thermostat was flipflopping between rooms, I couldn't delete one of the SRTs so couldnt delete the room and couldnt get heating. Deleted my home account and started again and now have heat (it was 12c in the living room this morning!)
I now have one SRT in the same room as the main thermostat and other in bedrooms kitchen etc. However the extension kit only calls for heat when the thermostat clicks into life. The kitchen is freezing because the living room where the main thermostat is, is up to temp, the SRT in the kitchen is set to 25c and shows 'heating to 25' in the app, but the boiler and pump are off.
All rooms have the extension kit as the zone controller, what am I missing?
I'm on a traditional setup with boiler, hot water tank and pump and Y valve for hot water/CH/hot water+CH
What am I missing?