TMG going to dump after creating code in 01 event to validate date fields.

Hi Abapers,

I have a simple requirement. I have a ztable with TMG created. Now i need to validate 2 fields namely date-from and date-to. If date-to - date-from is greater than 3 years i need to throw an error and block that record to get saved in the database. For that i have created an include in event 01 (before saving the data to database) with f_validate_entry and inside that i have written the below code. Now my issue is that not only its not working but TMG while entering data its going in a dump. I am sharing my complete code so that someone could help me where i am going wrong.

FORM CREATE_ENTRY .

DATA: IT_ZDATA TYPE STANDARD TABLE OF ZVEH_REG_CERTF,
LW_ZDATA TYPE ZVEH_REG_CERTF.
DATA: lv_date TYPE i.

LOOP AT TOTAL.

IF <ACTION> EQ 'N' OR <ACTION> EQ 'U'.

APPEND <VIM_TOTAL_STRUC> TO IT_ZDATA.

ENDIF.

ENDLOOP.

IF IT_ZDATA[] IS NOT INITIAL.

* Perform validation

LOOP AT IT_ZDATA INTO LW_ZDATA.

LV_DATE = LW_ZDATA-VALID_TO - LW_ZDATA-VALID_FROM.

IF LV_DATE > 1095.

MESSAGE 'Check the Validity period date range' TYPE 'S' DISPLAY LIKE 'E'.

VIM_ABORT_SAVING = 'X'.

EXIT.

ENDIF.

ENDLOOP.

ENDIF.

ENDFORM. " CREATE_ENTRY