Zoho Campaigns API - Send Campaign and "Content not reviewed"

Zoho Campaigns API - Send Campaign and "Content not reviewed"

Hi,

I successfully managed to create a Campaign with Zoho API and /createCampaign endpoint, receiving positive 200 status code and and a campaignKey, required for /sendcampaign. However, I can't send it via API, but instead always getting a response:
  1. {
      "code": "6611",
      "campaign_status": "Draft",
      "message": "Content not reviewed",
      "uri": "/api/v1.1/sendcampaign",
      "version": "1.1"
    }
for a request:

  1. https://campaigns.zoho.com/api/v1.1/sendcampaign?resfmt=json&campaignkey=<here-received-campaignKey>
ofc I'm attaching the access token to the Authorization Bearer header.

What am I missing?