Separator pages are usually attributes of the outq. You can create an outq that doesn’t add them to your output, or you can modify an existing outq:
CHGOUTQ OUTQ( mylib/myoutq ) JOBSEP(0)
There is a second outq attribute that might also be involved. If the previous change doesn’t do what you need, try this:
CHGOUTQ OUTQ( mylib/myoutq ) SEPPAGE(*NO)
One or the other of those, or both together, should work. If not, then more information will be needed.