Why is this lock going through when I am updating the file?

I have a CL trigger program on a file on an *INSERT *AFTER basis.  In this
trigger I am attempted to find out when this file is done being written.
I retrieve the &LIBRARY, &FILE and &MEMBER names from the Trigger Parameter
1, then attempt to lock the file thusly:

LOCKIT:     ALCOBJ     OBJ((&LIBRARY/&FILE *FILE *EXCL &MEMBER)) +     
                         WAIT(60)                                      
            MONMSG     MSGID(CPF0000) EXEC(DO)                         
            GOTO       CMDLBL(LOCKIT)                                  
            ENDDO                                                      

what is supposed to happen is this is supposed to go into an endless loop
until such time as no other operation has the file open.  However, it is
somehow getting past this code when I am still updating the file.

UPDDTA FILE(BSTONED/INRECX) MBR(BRECX001)

Here I hit F10 and insert a record (trying to emulate what the automatic
file receiving program is doing).  Every time I insert a record the file is
getting sent (one of the next lines is SNDNETF).

Any ideas why the program isn't waiting for the file to be locked?  Or why is
it allowing an exclusive lock on an open file?

Regards,

Jim Langston
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