Error message is displayed not on selection screen
<p>I have to display error message on the selection screen if data was not found, and I have to display this message directly on the selection screen. My problem is that it's displayed on blank screen.
This is my code:</p>

<pre><code>FORM 1main .
  CLEAR: gt_tbalv.
  PERFORM check_screen.
  PERFORM get_data.
  IF gt_tbalv IS NOT INITIAL.
    CALL SCREEN 100.
  ELSE.
*   Message Data not found
    MESSAGE e010 DISPLAY LIKE 'S'.
  ENDIF.
ENDFORM.                    " 1MAIN
</code></pre>

<p>Where is my mistake?</p>

<p>PS: I call this form from START OF SELECTION  event of selection screen </p>

<pre><code>************************************************************************
***                       START-OF-SELECTION                         ***
************************************************************************
START-OF-SELECTION.
  PERFORM 1main.
</code></pre>