Restore Subscriptions Unknow error

Q1. I'm having problems to restore my subscription​!

To solve this restore issue, please folow next steps:

Delete the current Project Viewer app.
Download and reinstall application from MAC Store

 
If an error message appears, please follow next steps:
Delete the current Project Viewer app.
Open the terminal
to locate Teminal use Search from Launchpad
launch.png
 
Type in Search box Terminal
t1.png
 
copy and paste this command: rm -rf ~/Library/Containers/com.Housatonic.Project-Viewer/  and then press enter. (This command clear the cache for application)
terminal.png
 
Restart the device.
Install the application from the app store.
Press the “Restore View-Only Subscription” button.​
restore.png