Cant reteive current set point zts 100

Cant figure out why this doesnt work with my thermostat id 3:

local working_target
working_target = luup.variable_get(‘urn:upnp-org:serviceId:TemperatureSetpoint1_Heat’, ‘CurrentSetpoint’,3)
luup.variable_set(“urn:upnp-org:serviceId:VContainer1”, “Variable1”, working_target, 48)

I have been able to write into Variable1 in another script… Why the get seems dont work properly ?

Thanks