Install Win 10 SDK if you don’t have:
In the AppxManifest.xml file of your converted application you will find an entry similar to the following one:
The value of the Publisher attribute should match the publisher id (CN=xxxxxxxxxxxxxxxxxxxxxxxxxxxx) of the Store account of your dev center:, for example.
After modifying the appxmanifest.xml, please use the makeappx.exe to package the application again:
C:\Program Files (x86)\Windows Kits\10\bin\x86>makeappx pack /d “C:\myapp\PackageFiles” /p c:\Output\myapp.appx