Error when send web socket to get Long-lived access token

After connect to websocket, login success by websocket, i send request to get long lived access token. But i met an error:
{“id”: 11, “type”: “result”, “success”: false, “error”: {“code”: 5, “message”: “Unknown error.”}}
this is my messge:
{
“id”: 11,
“type”: “auth/long_lived_access_token”,
“client_name”: “GPS Logger”,
“client_icon”: null,
“lifespan”: 365
}
this is topic: https://developers.home-assistant.io/docs/en/auth_api.html#long-lived-access-token