As you are using battery powered thermostats, to help us further resolving your issue, we need to know what receivers are being used. They may be near your manifold or boiler, however as we are not installers, it is impossible for us to tell you where they are in your premises.
Could you have a look at this list and let us know which receiver you are using?
UH8-RF (8 zone wiring centre, has UH8-RF labelled on the front cover)
UH8-RF V2 (Has 8 Zones and buttons for each zone, labelled UH8-RF V2)
RF Switch (has Boiler, CH1 and HW buttons, red power light on the right)
RF Switch V2 (has CH1, CH2 and HW, has red power light on the right)
RF Switch 16A (has Pair/Override button and a red power light on the right)
MiniHub Heating and Hot Water (has CH1, CH2 and HW and Power Pair button)
Lights may be red or green.
MiniHub OT (has CH1, CH2 and Power Pair button)
HC Switch (has Heat, Cool, Output and Pair buttons)