Managed Google Play
For release of FolderSync APK using your managed Google Play account the package name of the APK has to be globally unique. The APK file purchased has the same package name as for other customers and its package name is no available to use on managed Google Play. You can try to upload the APK but if it fails with an error, this is most likely the reason.
If you experience this issue and have no other means to distribute the APK, then the only option is to build the APK with a unique package name for your business.
For a fee or larger volumes orders we can offer to create a custom APK for you with a unique package name. Contact us to inquire further.