PR remstar auto A flex humidifier

Hi helpful CPAP people,
I've been using a CPAP for 13 years now. I'm new here, although I have visited the forum looking for answers in the past. My current issue is that the light-up numbers above the dial on my machine, that tell what level the humidifier is set at, are not lighting up anymore. I know how to push the button and toggle down to "backlit humidifier numbers" and then change the setting to "on", but this doesn't do the trick. I'm not sure if the numbers are just not working, or if the humidifier isn't heating up either. Any suggestions?
Thanks!

To check for whether the heater is even working....turn the knob to highest setting and let the machine run for about 15 minutes and remove the water chamber and check for warmth on the heating plate and bottom of the chamber.

How long have you had the PR S1 machine and humidifier? They have a 2 year warranty.
You might want to contact whomever supplied you the equipment if you can.