Error message when I want to save the automation

When I try to save an automation, I keep getting this message (see image). What causes this and how do I resolve it? Thanks for any response.

You could try to post the Yaml of your automation in here, as you might have made some mistakes, which causes this ( As the Warning Message says )
And if you have some Templates in the Automation, verify them in Developer Tools

thanks for your response

alias: "Opladers MQTT Beheer"
id: "opladers_mqtt_beheer"
mode: restart
trigger:
  - platform: state
    entity_id: sensor.opladers_monitor_ai
action:
  - repeat:
      for_each: "{{ label_entities('opladers') }}"
      sequence:
        - variables:
            obj_id: "{{ repeat.item.split('.')[1] }}"
        - service: mqtt.publish
          data:
            topic: "homeassistant/sensor/{{ obj_id }}_ai/config"
            retain: true
            payload: >
              {% if is_state(repeat.item, 'on') %}
                {"name": "{{ obj_id }}_ai", "state_topic": "homeassistant/sensor/{{ obj_id }}_ai/state", "unique_id": "uid_{{ obj_id }}_ai"}
              {% else %}
                ""
              {% endif %}
        - condition: template
          value_template: "{{ is_state(repeat.item, 'on') }}"
        - service: mqtt.publish
          data:
            topic: "homeassistant/sensor/{{ obj_id }}_ai/state"
            payload: "Actief"

Ok, Obviously i can't test those templates, and i don't use mqtt, hopefully someone else steps in

Okay, thanks anyway

It timed out waiting for something.
Not sure what.

Right, and as usual a deeper look in i.e RAW-Logs, and verifying templates could lead to some hint's

Consider the whole Action Sequence, im wonder why OP is not familiar with common troubleshooting procedures

And consequences of mode: restart , and trigger - platform: state

Note:Im not my self familiar with the repeat.item , but it feels like im seeing a never ending loop