function-module

I'm trying to use the function module REUSE_ALV_FIELDCATALOG_MERGE to pass the field label in ddic to display in the column header of the alv report. But, that didn't work. If I comment the I_STRUCTURE_NAME = 'TY_YNAH_CUS_OBJ_REQ' line, it give me runtime error state The ABAP program lines are wider than the internal table. But if I uncomment it ,the program still did not work REPORT YALV_TEST. tables sscrfields. type-pools : slis. "CREATE STRUCTURE -1 TYPES: BEGIN OF TY_YNAH_CUS_OBJ_REQ, REQID TYPE YNAH_REQ_ID, REQUESTOR TYPE YNAH_REQUESTOR, BUSINESS_OWNER TYPE YNAH_BUS_OWN, FUNCTIONAL_OWNER