`remind_state_invalid`

HTTP 409conflict

The first notification has not been sent yet.

Handling it

Fix the request and send it again. message says what is wrong, and param names the parameter where there is one. Keep the request_id: it lets Parasend find the request.

The error, as the API returns it

{
  "error": {
    "type": "conflict",
    "code": "remind_state_invalid",
    "message": "The first notification has not been sent yet.",
    "param": null,
    "request_id": "req_5e69684dc3de68bf8651a712"
  }
}