Host field value is changed after during a CALL

Hi guys,
 
Here' my problem:
 
I have three display formats and the @ECRAN field is the indicator to which 
format will be displayed.  EX: IF @ECRAN=01, Format "EC01WS" will be displayed.
Somewhere in the process, I read the options entered by the user in "EC01WS" 
and send the key values from the subfile to a Data Queue for further 
processing.  
 
If the user entered Option 2, I must show format "EC02WS".  So @ECRAN is 
changed from 01 to 02.  But then I call "QRCVDTAQ" to retrieve the key values 
so I can fill "EC02WS".  During that call, @ECRAN is set back to 01 wihtout any 
reason.
I know this behavior is not supposed to be.  I just don't why it is now.  
 
Could someone help me on this one?
 
thanks
 
Pascal Bellerose
Responsable exploitation de site TI/IT site manager
(418) 832-3507 ext: 8507
pascal_bellerose@xxxxxxxxxxxx
 
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