Honeywell evohome zoning issues

Hi

I've had the evohome system installed and am currently using 4 radiator valve heads (HR92) to create 4 separate zones in the kitchen, living room, bathroom and nursery. All the valves work and are turning on their respective zones. The strange issue I'm having is whenever I turn on any zone that 'ISN'T' the living room, the living room will also turn itself on and can't be switched off unless you turn the zone off that was turned on originally.

Just wondering if anyone else has had this issue or might know a fix.

Thanks