This issue usually occurs when the Download process is interrupted due to poor internet connection.
Step 1: Uninstall Voice PRO application from the Device.
Navigate to Settings> Apps> Voice PRO.
Click on Uninstall.
A confirmation pop-up will be displayed.
Navigate to Setting> Apps> Google Play.
Click on Clear Cache & Clear data.
Step 2: Install Voice PRO app on the Device.
Turn ON Device data/ Wifi.
Re-sync your Google Play account which you used for purchasing the Voice PRO app.
Download & Install Voice PRO app from Play store app.
On launching the app, you will have to allow access to the Internet for one time validation.
For more information, please contact our team at firstname.lastname@example.org.