What's up with my Apex PH probe?

[clhardy5]

My PH probe usually fluctuates a little through out the day - going down at night - up during the day. But since yesterday around 8PM it hasn't budged. Something seems off. Nothing went on in the tank - ie.....nothing was added/moved/messed with. ideas for a fix?

 

[landlubber]

same as most electrical devices, step one is reboot the system.
if i remember correct they must be kept wet to properly read. so if it dried out it might have other issues.