FSD_Control is required for service entry sheet(ML81N) GRN

1. Control is required for service entry sheet (ML81N)
Data Validation
In ML81N -while entering service entry sheet, we have to consider the possible validation with document date
(BLDAT_ESSR) & Reference document number (XBLNR _ESSR).
During entry of service entry sheet - ML81N, program has to checks the data in document date (fiscal year in
document date) & reference document number,
If the program found data duplication (reference document number and document date), immediately validation
enables the error message pop( Reference document already exists) by stopping of transaction further.