Conductivity probe / port defective?

Hi all, please advise with the conductivity probe.

Device is profilux 3 eX, with conductivity (also ph & temp) probes. Everything works great, except Conductivity.

It always reads 1.0mS, no matter what. Even when probe disconnected, same thing. It prompts me to think that conductivity port might be defective on the device itself? Is there anything I can do to troubleshoot it? Am I right thinking it's not a calibration issue since value is not inaccurate, it's just not present..?

I did factory reset on profilux, if it matters.

Thanks in advance!