Clob Field not Pulling Values(Menu item)

Hi

I have a task where I have to add a Text Field(CLOB) on the customer screen as a menu item(on right side)

So far this is what I accomplished

1.Added menu item and Enabled it in SETBOUT

2.Created a new screen(ZACLOB) with a CLOB field 

When I enter the values in the field on the ZACLOB screen,the script stores field value in rtf format in BPCustomer table in the customized field(ZCUSDES) but does not store populate the value of ZCUSDES when I go back to the screen ZACLOB

Pardon my Ignorance

My code to force [M:CLB]CLOB to display the value of [F:BPC]ZCUSDES

Subprog AV_CLOB(VALEUR)
Variable Clbfile VALEUR
If !Clalev([ZACLOB]) : Local Mask ZACLOB[CLB] Endif
If !Clalev([BPC]) : Local file BPCUSTOMER[BPC] Endif
[M:BPC0]ZCUSDES=[F:BPC]ZCUSDES
[M:CLB]CLOB=[M:BPC0]ZCUSDE

End

Thanks