Internal Twilio error for voice call StatusCallBack

Question

I am encountering an internal Twilio error (https://i.stack.imgur.com/Gej46.png) when handling StatusCallBack Events. I have a function that is supposed to update the status of outgoing calls, but it seems to be failing. I have tried debugging, but the breakpoint is not being hit. Twilio is returning a 500 error with the description '15000 ,internal twilio error'. This function was working fine until last Friday

This is my function(https://i.stack.imgur.com/FWScW.png) I was trying to get the status callback event from Twilio and update the call based on that event.

Here is my function for status callback

public async Task GetOutgoingCallStatus(CallStatusParams param)
{
    var conferenceSid = _callService.GetConferenceSidByParticipant(param.CallSid);
    if (param.CallStatus == "no-answer" || param.CallStatus == "busy" ||
        param.CallStatus == "canceled" || param.CallStatus == "failed")
    {
        var agentCallSid = _callService.GetAgentSidByConferenceSid(conferenceSid);
        var call = CallResource.Update(
                      twiml: new Twiml($"<Response><Say>{TwilioSettings.OutboundCallDeclineMessage}</Say><Hangup/></Response>"),
                      pathSid: agentCallSid
                 );
    }
    if (param.CallStatus == "in-progress")
    {
        await _callService.RaiseNotification(param.To, "OUTBOUND_CALL_RECEIVED");
    }
    if (param.CallStatus == "completed")
    {
        _callService.HangUpAllAgents(conferenceSid);
    }
}

The endpoint itself is not hit, so whatever the code in the function is not getting executed, which was getting executed before.