Netbox VM Object can`t set device to null or empty

[SchmidtJonathan1]

Hello,
I’m using Ansible to automate NetBox virtual machine objects. Now I have a use case where I want to remove the device assignment from a VM object. When I set the device parameter value to null, the device field remains unchanged on the object.
I’ve already tested this with the REST API using a PATCH request, and it works correctly with null.

Has anyone found a solution for this scenario?

I noticed that when the object already exists, its current value seems to overwrite my input, and I end up with an “OK” state without the desired change.

Example:

Input 1:

- name: Create virtual machine within NetBox with only required information
  netbox.netbox.netbox_virtual_machine:
    netbox_url: "{{ netbox_url }}"
    netbox_token: "{{ netbox_token }}"
    data:
      name: "test-vm2"
      cluster: "test-cluster"
      device: "test-device"
      custom_fields:
        os_specs: "debian10_64Guest"
        checkmk_agent_required: true
        checkmk_folder: "/"
        no_proxy: "no_proxy_server"
        proxy_address: "no_proxy_server"
    state: present

Output 1:

changed: [localhost] => 
    changed: true
    diff:
        after:
            state: present
        before:
            state: absent
    invocation:
        module_args:
            cert: null
            data:
                cluster: test-cluster
                comments: null
                config_template: null
                custom_fields:
                    checkmk_agent_required: true
                    checkmk_folder: /
                    no_proxy: no_proxy_server
                    os_specs: debian10_64Guest
                    proxy_address: no_proxy_server
                description: null
                device: test-device
                disk: null
                local_context_data: null
                memory: null
                name: test-vm2
                platform: null
                primary_ip4: null
                primary_ip6: null
                serial: null
                site: null
                status: null
                tags: null
                tenant: null
                vcpus: null
                virtual_machine_role: null
            headers: null
            netbox_token: VALUE_SPECIFIED_IN_NO_LOG_PARAMETER
            netbox_url: http://[url]:8000
            query_params: null
            state: present
            validate_certs: true
    msg: virtual_machine test-vm2 created
    virtual_machine:
        cluster: 10
        comments: ''
        config_context: {}
        config_template: null
        created: '2025-12-16T10:44:10.693614+01:00'
        custom_fields:
            checkmk_agent_required: true
            checkmk_folder: /
            checkmk_monitored_by: null
            cluster_name: null
            controller_type: null
            cpu_processor_type: null
            firewall_rules: null
            hosted_on: null
            no_proxy: no_proxy_server
            os_specs: debian10_64Guest
            os_type: null
            os_version: null
            proxy_address: no_proxy_server
            test: null
        description: ''
        device: 7
        disk: null
        display: test-vm2
        display_url: http://[url]:8000/virtualization/virtual-machines/329/
        id: 329
        interface_count: 0
        last_updated: '2025-12-16T10:44:10.693634+01:00'
        local_context_data: null
        memory: null
        name: test-vm2
        platform: null
        primary_ip: null
        primary_ip4: null
        primary_ip6: null
        role: null
        serial: ''
        site: null
        status: active
        tags: []
        tenant: null
        url: http://[url]:8000/api/virtualization/virtual-machines/329/
        vcpus: null
        virtual_disk_count: 0

Input device value null:

- name: Create virtual machine within NetBox with only required information
  netbox.netbox.netbox_virtual_machine:
    netbox_url: "{{ netbox_url }}"
    netbox_token: "{{ netbox_token }}"
    data:
      name: "test-vm2"
      cluster: "test-cluster"
      device: null
      custom_fields:
        os_specs: "debian10_64Guest"
        checkmk_agent_required: true
        checkmk_folder: "/"
        no_proxy: "no_proxy_server"
        proxy_address: "no_proxy_server"
    state: present

Output:

ok: [localhost] => 
    changed: false
    invocation:
        module_args:
            cert: null
            data:
                cluster: test-cluster
                comments: null
                config_template: null
                custom_fields:
                    checkmk_agent_required: true
                    checkmk_folder: /
                    no_proxy: no_proxy_server
                    os_specs: debian10_64Guest
                    proxy_address: no_proxy_server
                description: null
                device: null
                disk: null
                local_context_data: null
                memory: null
                name: test-vm2
                platform: null
                primary_ip4: null
                primary_ip6: null
                serial: null
                site: null
                status: null
                tags: null
                tenant: null
                vcpus: null
                virtual_machine_role: null
            headers: null
            netbox_token: VALUE_SPECIFIED_IN_NO_LOG_PARAMETER
            netbox_url: http://[url]:8000
            query_params: null
            state: present
            validate_certs: true
    msg: virtual_machine test-vm2 already exists
    virtual_machine:
        cluster: 10
        comments: ''
        config_context: {}
        config_template: null
        created: '2025-12-16T10:44:10.693614+01:00'
        custom_fields:
            checkmk_agent_required: true
            checkmk_folder: /
            no_proxy: no_proxy_server
            os_specs: debian10_64Guest
            proxy_address: no_proxy_server
        description: ''
        device: 7
        disk: null
        display: test-vm2
        display_url: http://[url]:8000/virtualization/virtual-machines/329/
        id: 329
        interface_count: 0
        last_updated: '2025-12-16T10:44:10.693634+01:00'
        local_context_data: null
        memory: null
        name: test-vm2
        platform: null
        primary_ip: null
        primary_ip4: null
        primary_ip6: null
        role: null
        serial: ''
        site: null
        status: active
        tags: []
        tenant: null
        url: http://[url]:8000/api/virtualization/virtual-machines/329/
        vcpus: null
        virtual_disk_count: 0