Error while running spectral fatigue analysis

I am getting following error while running "post-processing" spectral fatigue analysis:

"*** ERROR - MEMBER 2264-2265 NOT IN ORDER ON 8 POSTFILE

IT SHOULD PRECEDE - MEMBER 6842-6843

*** ERROR - MEMBER 9546-9547 NOT IN ORDER ON 8 POSTFILE

IT SHOULD PRECEDE - MEMBER 9842-9843

*** ERROR - MEMBER 9662-9663 NOT IN ORDER ON 8 POSTFILE

IT SHOULD PRECEDE - MEMBER 9844-9845

*** ERROR - MEMBER 6344-6345 NOT IN ORDER ON 8 POSTFILE

IT SHOULD PRECEDE - MEMBER 9762-9763

*** ERROR - MEMBER 6332-6333 NOT IN ORDER ON 8 POSTFILE

IT SHOULD PRECEDE - MEMBER 6920-6921

*** ERROR - MEMBER DATA ON POSTFILES OUT OF ORDER"

Any help would be highly appreciated.