mqtt.number not accepting unit_of_measurement

[leowinterde]

mqtt:
  number:
    - name: evcc_min_current
      unique_id: uniqueid__evcc_min_current
      icon: mdi:current-ac
      state_topic: "evcc/loadpoints/1/minCurrent"
      command_topic: "evcc/loadpoints/1/minCurrent/set"
      availability_topic: "evcc/status"
      min: 6
      max: 16
      step: 0.25
      unit_of_measurement: A