使用openXML创建模板演示文稿“.potx”的副本到新的“.pptx”

I have a powerpoint template with .potx extension, i need to create a copy of the template file, but the created file does not have any content present in it, it is a blank presentation, below is the function i am using to create a destination file using template file.I have a powerpoint template with .potx extensi