need help to call screen
i am making userexit.
if error message is than message should come and screen should not go for next screen.
IF int_mara-mtart = 'ZAMT' and i_mseg-BWART = '201'.
MESSAGE i001(zmsg1) WITH 'NO VALID '.
<b>how i can call screen which has given error message </b>
now what happing is that error message is coming but going for next screen.
but i want current screen only.