Not able to add proxypath while enabling product in extension of platform

I am trying to build sample extension.
All steps has been done.
But while enabling product in extension in platform, it is giving me error.
I checked through debugging the code.
I found that while adding new proxypath it is giving already another proxy path is added.
So not able to add this new one. I was tried delete it but not able to do.
Due to this, I am not able to see my changes on product description page.
need help to sort out this.

@milankamboya Uninstall your extension and Install the extension again. This will resolve the proxy path issue.