Message type: E = Error
Message class:  HRPSGB_HER - HR PS GB Higher Education Messages (USS, HESA etc) 
Message number: 303
Message text: Only one occurrence of 02, 03, 04 or 05 can apply at same time
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The SAP error message HRPSGB_HER303 indicates that there is a conflict in the assignment of certain infotypes in the Human Resources module, specifically related to the handling of employee records. This error typically arises when there are multiple occurrences of infotypes 02 (Personal Data), 03 (Payroll Status), 04 (Organizational Assignment), or 05 (Address) that are overlapping or incorrectly configured.
Cause: The error occurs when: There are multiple active records for infotypes 02, 03, 04, or 05 for the same employee at the same time, which is not allowed. The system is trying to create or modify an infotype record that conflicts with existing records. The infotype records have overlapping validity periods.
Solution: To resolve this error, you can take the following steps: Check Existing Infotype Records: Use transaction code PA20 (Display HR Master Data) or PA30 (Maintain HR Master Data) to review the infotype records for the employee in question. Look for any overlapping records for infotypes 02, 03, 04,
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