User exit to display Vendor Name in F110 - Payment Run in FI

When Automatic Payment Program is run (T.Code F110), the Text fields in Vendor Line should have "Payment" written and G/L Line should display the Vendor Name.

In Tcode - OBBH
Make a substitution rule with prerequisite - 
Transaction code F110 (BKPF-TCODE = F110)

Subsitiution - Exit on BSEG-SGTXT and call U903.

Go to program RGGBS000 and modify it.

Add the following code to the form get_exit_titles

EXITS-NAME = 'U903'.
EXITS-PARAM = C_EXIT_PARAM_NONE.
EXITS-TITLE = 'Vendor and G/L Line'.
APPEND EXITS. 

and

Create a form below-

FORM U903.

DATA: L_NAME TYPE LFA1-NAME1.
DATA: V_LIFNR TYPE LFA1-LIFNR.
DATA: V_BELNR TYPE BKPF-BELNR.

IF BSEG-KOART EQ 'K'.
  BSEG-SGTXT = 'PAYMENT'.
  V_LIFNR = BSEG-LIFNR.
  EXPORT V_LIFNR TO MEMORY ID 'LIFNR'.
ENDIF.

IF BSEG-KOART EQ 'S'.
  IMPORT V_LIFNR FROM MEMORY ID 'LIFNR'.
  SELECT SINGLE NAME1 INTO L_NAME FROM LFA1 WHERE
    LIFNR = V_LIFNR.
  IF SY-SUBRC = 0.
    MOVE L_NAME TO BSEG-SGTXT.
  ENDIF.
  FREE MEMORY ID 'LIFNR'.
ENDIF.

ENDFORM.                                "U903