chart name not saved when save as another file

Hello,
Could anyone help me with this:
I have a EXCEL file includes charts, when I use the following in macro
to save as another file, the chart names are not saved in the new
file, all the chart names becomes Chart1 Chart2 etc. I checked the
origioanl file in Chart Tools, Layout, Properties, the chart names are
the names appear in the tabs, not "Chart1", "Chart2" etc. Why the
chart names are not saved?

ActiveWorkbook.SaveAs Filename:= _
"S:\DataStructure\IWRS.xlsm", _
FileFormat:=xlOpenXMLWorkbookMacroEnabled, CreateBackup:=False

Thanks a lot.

Haley