Message type: E = Error
Message class:  HRPAO_TIMEDATA - Messages for Time Infotypes in PAO (s. a. HRPAO_ABSENCE) 
Message number: 051
Message text: Values have not been changed
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The SAP error message HRPAO_TIMEDATA051 typically indicates that there is an issue with the time data for an employee in the Human Resources (HR) module. The message "Values have not been changed" suggests that an attempt was made to update time data, but the system did not detect any changes to the values being submitted. Causes: No Changes Made: The most common cause is that the values being submitted for the time data are identical to the existing values in the system. Therefore, the system does not process the update. Incorrect Data Entry: There may be an issue with how the data is being entered or processed, leading to the system not recognizing any changes. Authorization Issues: The user may not have the necessary permissions to make changes to the time data, which could prevent updates from being processed. System Configuration: There may be configuration settings in the HR module that are preventing changes from
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