Post Election Edit fast formula always return seeded message

Summary:

Post Election Edit fast formula always return content of seeded message BEN_92187_POST_ELCN_NOT_PASS. We are trying to return custom message at Post Election Edit fast formula. We have written as simple FF just to return custom message but is is always failed. below are text of FF

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SUCCESSFUL = 'N'

ERROR_MESSAGE = 'error'

l_status = add_rlog(-1,-1,'BEN_FF_ELIG_CALC_SUCCESSFUL ='||SUCCESSFUL)

l_status = add_rlog(-1,-1,'BEN_FF_ELIG_CALC_SUCCESSFUL='||ERROR_MESSAGE)

return SUCCESSFUL,ERROR_MESSAGE

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Instead of printing error it is printing "There was a problem saving the enrollment."