- reset stream to position 0 before loading

GBase/DataHandling/XmlDataReader.cs

@@ -40,6 +40,7 @@ namespace GBase.DataHandling
             if (typeName == null)
                 throw new ArgumentNullException(nameof(typeName));
 
+            file.Seek(0, SeekOrigin.Begin); //reset stream to it's beginning to be able to load it
             XDocument xmlDocument = await XDocument.LoadAsync(file, LoadOptions.None, cancellationToken);
             file.Seek(0, SeekOrigin.Begin); //reset stream to it's beginning to be able to save it