Template not showing attribute

Hi

I am trying desperately to understand templating but can not get the field “nexton” template to work its driving me crazy as first two worked fine

Any help would be appreciated

custom_fields:
power: >
[[[
return <ha-icon icon="mdi:flash" style="align-self: start; justify-self: start; width: 12px; height: 12px"> </ha-icon><span>${Math.round(states[variables.power_entity].state)} W</span>
]]]
energy: >
[[[
return <ha-icon icon="mdi:flash" style="align-self: start; justify-self: start; width: 12px; height: 12px"> </ha-icon><span>${Math.round(states[variables.energy_entity].state)} kWh</span>
]]]
nexton: >
[[[
return “state_attr(‘schedule.pool_schedule’,‘next_event’)”
]]]