Clearing Alerts in Orion.AlertActive

Hey guys,

I'm trying to clear alerts in SWQL. My code is as follows:

public static bool Clear(IEnumerable<Alert> alerts)

        {

            var ids = alerts.Select(alert => alert.AlertObjectID).ToList();

            var body = JsonConvert.SerializeObject(ids);

            var postAlert = _Post(body, "Invoke/Orion.AlertActive/ClearAlert");

            if (false == postAlert.HasData) return false;

            return Convert.ToBoolean(postAlert.Data);

        }

I have a similar method to acknowledge alerts and it works fine with Invoke/Orion.AlertStatus/Acknowledge.

Why is clearing the alerts not working (getting 400 error)? I'm sending in an array of AlertObjectIDs?