I am trying to use the Requests REST api to call the following (and through the GameSparks requests page (and postman also)

https://<apikey>.live.gamesparks.net/rs/<credential>/<Secret>/LogEventRequest


body is

{
  "@class": ".LogEventRequest",
  "eventKey": "RequestPlayerData"

}

However I always get response of

{
  "@class": ".LogEventResponse",
  "error": {
    "authentication": "NOTAUTHORIZED"
  }
}

I've tried numerous combinations of credentials, which have permissions to make REST calls, but always getting "NOTAUTHORIZED"