Huh!? It's not supposed to do that!
So what I hear you saying is that you have a meter that is permanently stuck with the NIST standard curve settings and you can't change away from the 6.86 one? Can you get the NIST standards instead? Or does your calibration buffer/standard have '7.01' on the package?
Hrm. I'm going to go find the manual and link to it. Hopefully this is a simple issue where you have to hit something else before 'mode', like actually be in the calibration/standardization window and it will work.
Can you send the thing back?

Okay here is the link:
http://www.pmtac.org/download/HANNA/98129_98130.pdf