Based-on member control list error

With the help of everyone that has responded to my earlier message, this 
project is moving along. 
I now need help updating my file.  When I try to update the file I get the 
following message:

**
Message ID . . . . . . :   CPF5153                                           
 Date sent  . . . . . . :   02/11/04      Time sent  . . . . . . :   08:44:52 
                                                                              
 Message . . . . :   Member SLJOIN has more than one based-on member.         
                                                                              
 Cause . . . . . :   Member SLJOIN file SLJOIN in library TESTFILE has more   
   than one based-on member; therefore, the control list must specify which   
   based-on member to use.                                                    
 Recovery  . . . :   Specify either a record format name, or a record format  
   name and member number in the control list.  Then try the request again.   
**

I have enclosed example of my file and the select/update part of the RPG 
program. What I need to know is what am I overlooking?  Any and all help would 
be appreciated.
Willie...

FILE**
*             R DS                        PFILE(TESTFILE/SLDS) 
           K DSRCID                                         
           K DSFIL1                                         
           K DSORDN                                         
           K DSITMN                                         
 *                                                          
           R MM                          PFILE(TESTFILE/SLMM) 
           K MMRCID                                         
           K MMFIL1                                         
           K MMORDN                                         
           K MMITMN                                         
 *                                                          
RPG Program**

IORDWRK  NS  04   1 CM   2 CM                             
I                                        9  10 ITEMNO     
I                                       11  16 MATNO      
I                                       17  263QUORD      
I                                       27  28 UNIT       
I                                       29  43 SIZE       
I                                        1 192 MM   

 IORDWRK  NS  05   1 CD   2 CS                         
 I                                     1 192 DS     

 C                     MOVEL'MM'      WRKKEY         
 C WRKKEY    CHAINORDWRK               45
 C   45              GOTO NOMOR                    
 C                     EXCPT                         
 C                     SETOF                     04  
 C                     MOVEL'DS'      WRKKEY         
 C WRKKEY    CHAINORDWRK               45                    
 C                     EXCPT                         
 C                     SETOF                     05  
 C*

 OORDWRK  EADD     04                       
 O                         MM            192     
 O                                                3 ' ' 
 O                         NEWNUM     8     
 OORDWRK  EADD     05                       
 O                         DS             192     
 O                                                3 ' ' 
 O                         NEWNUM     8