Configuration Solar Pump Control

I posted on the 17th June under ESPHome, Pump Control, which I have now sorted thanks to the members there. I now have a problem with the Configuration.yaml. In Notifications I get the message
“Invalid config” the following integrations and platforms could not be set up: sensor.template .
As before any help in resolving the error is much appreciated.
Code here

sensor: 
  - platform: template
    sensors:
      temp_diff:
        friendly_name: "temperature_difference"
        value_template: >-
          {% if ((states.sensor.panel_temperature.state | float ) - (states.sensor.tank_temperature.state | float))
            < (states.input_number.pump_on_offset.state | float ) %} pump_off
            pump_off
          {% elif ((states.sensor.panel_temperature.state | float ) - (states.sensor.tank_temperature.state | float))
            > (states.input_number.pump_on_offset.state | float ) %}
             'pump_on'
          {% else %}  
             'pending'
          {% endif %}

input_number:
  pump_off_offset:
    name: Pump OFF offset
    initial: 0.1
    min: 0
    max: 2
    step: 0.1

  pump_on_offset:
    name: Pump ON offset
    initial: 0.5
    min: 0
    max: 2
    step: 0.5

automation:
  - id: ID13
    alias: 'Pump hot water if hotter than tank - stop if not'
    initial_state: 'on'
    trigger:
      platform: state
      entity_id: sensor.temp_diff
    action:
      entity_id: switch.solar_pump
      service_template: >-
        {% if is_state ('sensor.temp_diff' , 'pump_on') %} switch.turn_on
        {% else %} switch.turn_off {% endif %}