From the control panel, navigate to:
Settings > Print > Layout > Collate
Touch On [1,2,1,2,1,2].
Print the document.
Is the document collated correctly?
The problem is solved.
Go to step 2.
From the document that you are trying to print, open the Print dialog, and then select Collate.
Go to step 3.
Reduce the number of pages to print.
Are the pages collated correctly?
Contact customer support.