well, to only say “didn’t worked” does not help very much, does it?
as I understand your issue, you already uploaded an app to Google Play and now you like to change the package name and upload an update of the same app. Is this correct?
So in case I unnderstand you correctly, then as already said, this is not possible, you have to keep the existing package name! But of course you can use Appybuilder to create the update