Google script to send weekly summaries of Google calendar events

gistfile1.js

EMAIL = "[email protected]";
CALENDAR = "calendarname";

function weeklyReminder() {
  var StartDate = new Date();
  var StartDateDD = StartDate.getDate() + 1;
  // Months are based on 0-11 so +1
  var StartDateMM = StartDate.getMonth() + 1;
  var EndDateDD = StartDate.getDate() + 7;
  // Across months, the date will get messed up so...(NEEDS TESTING!)
  if (EndDateDD > 31) {
    var EndDateMM = StartDateMM + 1;
    EndDateDD = EndDateDD - 31;
  }
  else {
    var EndDateMM = StartDateMM;
  }
  
  var EndDate = new Date(StartDate.getYear(), EndDateMM, EndDateDD);
  var cal = CalendarApp.getCalendarById(CALENDAR);
  var weeklyEvents = cal.getEvents(StartDate, EndDate);
  
  var eventTitle = [];
  var eventStartTime = [];
  var previousStartTime = new Date(1970);
  var eventEndTime = [];
  var eventDescription = [];
  var eventLocation = [];
  var message = "<h1>Weekly Events</h1>";
  
  for (var i = 0; i < weeklyEvents.length; ++i){
    eventTitle[i] = weeklyEvents[i].getTitle();
    eventStartTime[i] = weeklyEvents[i].getStartTime();
    eventEndTime[i] = weeklyEvents[i].getEndTime();
    eventDescription[i] = weeklyEvents[i].getDescription();
    eventLocation[i] = weeklyEvents[i].getLocation();
    // If there are multiple events on same day, dont print the date out more than once
    if (eventStartTime[i].getMonth() == previousStartTime.getMonth() && eventStartTime[i].getDate() == previousStartTime.getDate() && eventStartTime[i].getYear() == previousStartTime.getYear()){
        message = message + 
        "<br><u><b>" + eventTitle[i] + "</b></u><br>" + 
        "<font color = 'red'>" + formatTime(eventStartTime[i]) + " – " + formatTime(eventEndTime[i]) +"</font><br>" + 
        "<i>" + eventDescription[i] + "</i><br>";
    }
    else {
        message = message + 
        "<hr noshade width='75%' align = 'left'><h3>" + ((eventStartTime[i].toDateString()).slice(0,10))+ ":</h3>" +
        "<u><b>" + eventTitle[i] + "</b></u><br>" + 
        "<font color = 'red'>" + formatTime(eventStartTime[i]) + " – " + formatTime(eventEndTime[i]) +"</font><br>" + 
        "<i>" + eventDescription[i] + "</i><br>";
    }
    previousStartTime = eventStartTime[i];
  }
  
  if (weeklyEvents.length == 0){
    message = "There are no events/someone forgot to put any events in the calendar for this week.";
  }
  MailApp.sendEmail(EMAIL, "Events: " + StartDateMM+"/"+StartDateDD + "–" + EndDateMM+"/"+EndDateDD, message, {htmlBody: message});
}


// Converts 24 hour based time to 12 hour
function formatTime(date) {
  var d = new Date(date);
  var hh = d.getHours();
  var mm = d.getMinutes();
  var mod = "AM";
  
  if (hh >= 12){
    hh = hh - 12;
    mod = "PM";
  }
  
  if (hh == 0){
    hh = 12;
  }
  
  mm = mm < 10 ? "0"+mm : mm;
  
  return (hh + ":" + mm + " " + mod);
}

I would like to use this code, exactly what I need! Unfortunately, when using the script with EMAIL = address to send to and CALENDAR = google calendar ID, I get the error message Exception: Event start time must be before event end time. (line 21, file "Code").

There seems to be an issue with the part var weeklyEvents = cal.getEvents(StartDate, EndDate);. Any idea how to overcome this?