Not able to create video with v2 endpoint

Trying your API without a subscription for now and getting the status "failed" with this error:
{ "code": 40010, "detail": "Please subscribe to higher plan to generate higher resolution videos", "message": "Video format not supported" }

The payload:

    video_inputs: [
      {
        character: {
          type: "avatar",
          avatar_id: "Angela-inblackskirt-20220820",
          avatar_style: "normal",
        },
        voice: {
          type: "text",
          input_text: "Welcome to HeyGen API.",
          voice_id: "1bd001e7e50f421d891986aad5158bc8",
          speed: 1,
        },
      },
    ],
    test: true,
    aspect_ratio: "16:9",

What does this error exactly mean?
Can I test this endpoint without a subscription?
Should I change the resolution of the video to make it work?