V3 API: Segments not visible, html message not possible

Hi! I have 2 questions regarding the v3 API:

  1. Segments not visible:
    I created some new segments. But segments are not visible in the response using endpoint https://{youraccountname}.api-us1.com/api/3/segments. Instead of my created segments I see some pre defined segments which are not available in my dashboard. I double confirmed I am using the API credentials from my account.

  2. I tried to create and send HTML campaign to lists/segments. I used https://{youraccountname}.api-us1.com/api/3/messages for creating an HTML message. But there is no option in the message object (Create a message) for creating HTML message. I added html key inside the message object myself for test and it seems HTML message is created. But I could not find any instruction to use the message to create and send campaign in the documentation (Create Campaign). I tried to pass the message_id, list_ids in the payload of https://{youraccountname}.api-us1.com/api/3/campaign But response says message_id, list_ids parameters do not exist.