Error: ENDMETHOD missing, when using a FORM on a BSP Event handler

Hello,

In my ONREQUEST event I have the following FORM

FORM REPLACE_STRING USING STRING TEMPLATE NEW.

CALL FUNCTION 'SDIT_REPLACE_STRING'

EXPORTING

IN_STRING = STRING

NEW = NEW

TEMPLATE = TEMPLATE

IMPORTING

OUT_STRING = STRING.

ENDFORM. "REPLACE_STRING

However when running a check on the code I get the error:

"Statement ENDMETHOD is missing"

Is it not possible to use a FORM in the event handler in a BSP?