curl --request POST \
  --url https://api.eu.bronto.io/groups/{groupId}/members \
  --header 'Content-Type: application/json' \
  --header 'X-BRONTO-API-KEY: <api-key>' \
  --data '
{
  "members": [
    {
      "member_type": "USER",
      "member_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
    }
  ]
}
'

{
  "code": 499,
  "type": "Not Found",
  "correlation_id": "<string>",
  "details": "Resource not found."
}