OKI Pro 8432WT color print issue

One of our customer owning  OKI Pro8432WT  has issues with printing. Apparently it seems like the colors are faded out , please see sample attached.  Also attached is a Photo of the original doc for reference. Would you please advise on troubleshooting and steps to resolution here?

Solution:It appears that printer mode may be set to  “White ON” , below is snippet from the manual to change the modes.