How do I add data in connector type fields through API?

Hi, I'm starting API development. I'm able to create a card through my environment using GraphQL, but I'm not able to add data to a connector type field. Field information:

 {
          "id": "contatos",
          "type": "connector",
          "index_name": "field_29_connector",
          "description": "",
          "label": "Contatos:",
          "allChildrenMustBeDoneToFinishParent": false,
          "canConnectExisting": true,
          "connectedRepo": {}
        },