Using Method UPDATE_CONTRACT_OBJECT to Update Facts Value

Hello,

I'm using method  UPDATE_CONTRACT_OBJECT to update Fact Values.

I want to update the content of IT_FACTS-BAPI_CTRACPSOBJECT_FACTS-VALUE_GENERIC  from the FormBundel Header SYS_FORM_BUNDEL_HEADER-PERIOD_KEY.

After generating the funtion, my mapping is modify by the generation program to T_FACTS-BAPI_CTRACPSOBJECT_FACTS-VALUE_GENERIC = CURRENT_DATE.

This generates an error message in the method due to existing controls in BAPI_CTRACPSOBJECT_CHANGE.

There is any way that I could avoid the generation programme to overwrite the mapping? I just want to transfer the value of the period (4 Characters-Ex: 2014) to VALUE_GENERIC?

Thank you in advance

Regards

Carlos