curl --request POST \
  --url https://api.liderhub.ai/v1/groups/{group}/admins \
  --header 'Content-Type: application/json' \
  --header 'x-company-key: <api-key>' \
  --data '
{
  "action": "promote",
  "phones": [
    "5491123456789"
  ]
}
'

{
  "connection": "aaaaaaaa-bbbb-cccc-dddd-111111111111",
  "success": true
}