Unable to find service media_player/volume_set

After upgrading from 0.39.3 to 0.41.0 I get the following message
WARNING:homeassistant.core:Unable to find service media_player/volume_set

I believe this is related to the following automation:

- alias: Adjust TV Volume via slider
  trigger:
    platform: state
    entity_id: input_slider.tv_volume
  action:
    - service: media_player.volume_set
      data_template:
        entity_id: media_player.tv
        volume_level: '{{ float(trigger.to_state.state) / 100 | round(2) }}'
- alias: Adjust TV Volume slider
  trigger:
    platform: state
    entity_id: media_player.tv
    # value_template: '{{ state.attributes.volume_level }}'
  action:
     service: input_slider.select_value
     entity_id: input_slider.tv_volume
     data_template:
      value: '{{ states.media_player.tv.attributes.volume_level * 100 | int }}'

What I can’t figure out is why? The slider/automation works.

I also get the following message:
WARNING:homeassistant.helpers.condition:Value cannot be processed as a number: unknown

Can someone help me troubleshoot this?

It has been a long time since you asked this question but just for the sake of helping others, I found this solution in another thread:

volume_set:
  service: media_player.volume_set
  data_template:
    entity_id: media_player.receiver
    volume_level: '{{ volume_level }}'