Thank you for posting in the Community.
I'd be happy to look further into this for you. Can you please let me know what issue you are facing while creating a ticket?
Thank you for your response. In order to troubleshoot this issue further, we will have to take a closer look at your setup and will require access to your site to look into your GPA calculation method, and how it is being calculated based on the GPA Points on your Grade scale. We will have to make sure that all the stored grades were stored using the GPA points, based on the Grade scale at the District Setup.
I see that you have a support case opened with the PowerSchool SIS Support team, I recommend continuing working with them as they will be in a better position to assist you further with this since they can access your site to look into your setup.