Google Drive API v3 Permissions sendNotificationEmail: False -Not Working

Question

I am utilizing the Permissions endpoint call of the Google Drive API v3 to assign reader and writer status to a folder within app scripts for a shared google drive. The main goal is to not send the notification email when the permission is shared with a user. I have included the parameter 'sendNotificationEmail: false' in the body of the request however the email is still being sent notifying the user. The code snippet that I am using is below. Am I including the 'sendNotificationEmail' parameter in the wrong part of the request?

if (currTabName == "Testing" && curRange.getColumn() == 2){
   for (var i = row; i < (row+rows); i++) {
     var Email = currSS.getRange(i,2,1,1).getValue();
     try{
      var url = 'https://www.googleapis.com/drive/v3/files/FileID/permissions';
      var data = {
        'role': 'writer',
        'type': 'user',
        'sendNotificationEmail': false,
        'emailAddress': Email,
        'supportsAllDrives': true,
      }
      var options = {
        'method'     : 'POST',
        'contentType': 'application/json',
        'headers'    : { Authorization: 'Bearer ' + 'yourAccessToken' },
        'payload'    : JSON.stringify(data) // Convert JavaScript object to JSON string
      };
      var response = UrlFetchApp.fetch(url, options);
      Logger.log(response);
     }
     catch(err) {
       Logger.log(err.message);