Here are some directions to help you get past that issue:
The recommended approach for accessing PowerSchool for your district on the mobile app is through “Where’s my District Code?” link within the sign in screen in the mobile app. Please see the steps below.
From the mobile app, click Where’s my District Code.
On the menu that opens, click Enter Server Address.
In the Server Address box, for the Vinton-Shellsburg School District, enter the following:
A popup may ask if your District Location is in Canada, confirm No.
Login using your credentials.
To learn more about the PowerSchool Mobile App and how it can benefit you, you can learn about that here.
Please let me know if you have further questions.