I am trying to edit the values of an xml document following the instructions found on another post here How to modify existing XML file with XmlDocument and XmlNode in C# .

here is my code

XmlDocument xml = new XmlDocument();
        xml = xml.Load(@"https://www.aade.gr/sites/default/files/2020-09/SampleXML_1.1%20%20(ΤΙΜ-