@PatrickM0783  

The error you're encountering in Pega suggests that the system is unable to access or resolve the property `.pxPages(AddressesPL).City` because it doesn't recognize the class or the property at runtime. Here's a breakdown of how to address this issue:

 Possible Causes and Fixes:

1. Class Reference Issue:    - The error message mentions `Class:null`. This indicates that Pega is unable to determine the class of the page or property you are referring to in the Data Page.    - Double-check the class of the Data Page you're using to ensure that it's correctly defined and populated. The property `.pxPages(AddressesPL).City` needs to be valid for the class type used by the Data Page. If `AddressesPL` is a list or page group, make sure it’s properly initialized and contains the property `City` at runtime.

2. Correct Page Reference:    - In your Activity step `@Baseclass.pzSortClipboardData`, verify that the property path you’re accessing is correct. If you're trying to access a page property within a repeating grid or table, confirm that `.pxPages(AddressesPL)` correctly points to the data that has been populated from the Data Page.    - Ensure that `AddressesPL` is not null or empty and that the page structure has been properly instantiated before the Activity is executed.

3. Property Access:    - If you’re accessing a property in a repeating grid (which could be a list of pages), ensure that the property `City` exists on the page referenced by `AddressesPL`.    - Check if the property `City` is defined correctly in the class associated with the Data Page. If it's a dynamic property or calculated field, ensure that the value is available before trying to use it in the sorting logic.

4. Data Page Scope and Mode:    - Since the Data Page is scoped to "Requestor" and set to "editable," check if the data is being correctly loaded into the clipboard. Sometimes, changes made to the Data Page might not be reflected in the clipboard immediately, especially when dealing with complex sources like Report Definitions.    - Ensure that the Data Page has been refreshed and contains the expected data before Step 2 of the Activity is executed.

5. Sorting Mechanism:    - In the UI, if you’re triggering the sort by "City", ensure that the sorting logic correctly handles the data coming from the Data Page. The error might occur if the sorting function cannot find the property on the pages in the table. You may need to review how the sorting logic is executed in the Activity and check that the correct property (in this case, `City`) is being referenced.

Steps to resolve:

- Check the Data Page: Review the Data Page source (Report Definition) and make sure that the `AddressesPL` page list is being populated correctly and contains the `City` property. - Validate Property Paths: Double-check the property reference `.pxPages(AddressesPL).City` to ensure it is pointing to the correct data. - Ensure Proper Initialization: Make sure that the data is available in the clipboard when Step 2 of the Activity is executed. - Review Activity Logic: Examine the logic in `@Baseclass.pzSortClipboardData` to ensure that it is properly handling the property and page references.

If none of the above steps resolve the issue, I recommend checking the system logs to get more specific details about the error, which might help you pinpoint the exact source of the problem.