XML files not updating on web page

I upload several XML files. Each web page has code to read it’s specific XML files and load the data into HTML tables in the web page.
For instance - web page for “player stats” (PlayersMonthly.html) uses 3 xml files. uDates.xml to load current date info… uPlayersMonthly.xml to grab players monthly stats, and uPlayersYearly.xml to load load player’s year-to date data. All the xml files are written by an excel spreadsheet used to compile daily stats. Then the xml files are uploaded to site with FTP. The XML file names DO NOT CHANGE. Only the data in the file changes. Therein I believe is the problem. Upon 1st run the site loaded all the xml files fine. When the xml file data changes, the web pages still only use the data from the 1st xml file reads. Not the new data. I suspect there is something caching the 1st xml file read and then not realizing the data has changed.(It’s NOT my browser cache.) Normally I would suspect coding error, however the same pages work fine on my computer and worked fine on our previous two sites that went belly up.
I attempted deleting the uFiles before uploading them again but made no difference.
Code that inserts uPlayersMonthly.xml into PlayersMonthly.html
Load xml code:

xmlhttp.send();
xmlDoc=xmlhttp.responseXML;
var x=xmlDoc.getElementsByTagName("tabledata");
Looping Code to insert xml data into HTML table in page.
for (i=0;i<x.length;i++)
  {
  document.write("<tr><td>");
  document.write(x[i].getElementsByTagName("rank")[0].childNodes[0].nodeValue);
  document.write("</td><td>");
  document.write(x[i].getElementsByTagName("name")[0].childNodes[0].nodeValue);
  document.write("</td><td>"); 
<!.................and so on.>
</script>
</table>

Feel free to edit the the data in uDates.xml and uPlayersMonthly.xml. for any testing.