Google Script not Appending Spreadsheet

I'm trying to write a little script to make my coworkers and mine lives easier. I am trying to append lines to a spreadsheet based on information entered into a custom form. The code posted below just the doPost block which should be appending the google spreadsheet.

function doPost(form) { 
  var PN = form.PartNumber;
  var REV = form.Revision;
  var DATE = form.RevisionDate;
  var DESC = form.Description;
  var NOTE = form.PartNotes;
  var URL = form.myFile.getURL();  
  var ss = SpreadsheetApp.openById("ID HERE"); // removed ID for sake of safety (let me be paranoid)
  var sheet = ss.getSheetName('Uploads');
  sheet.appendRow([PN,REV,DATE,DESC,NOTE,URL]);
}

I am unsure why it isn't writing to the spreadsheet but it isn't throwing me any errors. If you can offer any insight as to what is wrong I would greatly appreciate it; there are many guides online but most seem to be based on deprecated functions/code/etc.

Thanks for your time.