I think the issue is in the way you are constructing the itemURL:
var itemURL=siteURL +'/Lists/'+changeList+itemID + '_.000';
The '_.000' part shouldn't be there, I don't think.
M.
var itemURL=siteURL +'/Lists/'+changeList+itemID + '_.000';
The '_.000' part shouldn't be there, I don't think.
M.