Doesn't the float valve on the water sump control the level of water in the sump?

Do you have water to the valve? (Like loose the nut on the tubing-- does water come squirting out?)

If not, you can't get humidity into your system, without water in that sump or pan!
The mat can be turning-- but if it is not SOAKING WET!-- you get no humidity in the house!.

Could the main shut off valve be plugged?--

Bottom line is-- the Humidifier needs a steady supply of water-- It will go thru gallons of water every day, this time of the year!

Mack B