While processing the salary change for employees, in Compensation Info, it considers only the hiring data to calculate the different rather than the most recent entry in the portlet.
In the above screenshot shows, the increase of this pay component is from null to 10. But in employee's data, only while hiring it was null. After that there are more 10 different entries in different dates with increase to 10. But in every entry this shows as null to 10 increase. This change was initiated to increase another pay component. So this component should not show value increase as this.
I believe this an EC Comp Info question so would you mind removing the SAP Compensation tag which a separate module ?
Also have you heard of the P1 incident post 2H 2023 release where a lot of onHire and onInit rules in Comp Info portlet are not working any more for various business cases ? This could be tied to it. It is being actively worked on by SAP engineering.
All the best