There are two "Clutch switches" - the one I spoke of extends it's plunger, the other one "shorts out" when you press the clutch down all the way and is for the Starter - when you push in the Clutch.
So the one I'm referring to is the one that starts this idle up - otherwise when the Clutch is released - all the way back to rest (up), that plunger is shoved all the way into it's stop in the housing and signals to the system "off" - there is a flange/button that acts as a "stopper" to rest on the mounting flange that the switch is mounted on. The Clutch pedal runs a Master/Slave system, so there is a return spring which keeps that clutch pedal in the up position and the Idle-up plunger in all the way.
So if the Clutch is not idling up and you remember when it used to, there are a set of switches on the Brake side as well.
One cancels the Cruise Control - the other lights the brake light for Stop when you press on the Brake pedal.
IF the aspects of the two sets of switches (Clutch-side is one set or pair; Brake is another pair) is not right, this also prevents you form using Cruise Control (If equipped) and will fight you for Starting the car - the Clutch plunger aspect is not right - so you'd have starter issues.
You don't; at least you're not telling us - which means, either the system is not thinking you need to use Idle up - or the dealer needs to check that system and make sure the aspects of all four switches are correct so it can idle up when it is supposed to.
The system is smart enough to cancel the Idle up is it does not detect a lot of stalling or near-stall conditions - as if you're doing it right. It can turn off the "idle up" if specific conditions are being met.
So you'll have to make some choices - either way requires an effort or some $$$ to spend to have someone check it.
You can do this yourself but this requires knowing that you have a working Cruise control, and when you start the car - you're not getting a message telling you to Press Brake and Clutch to Start. The dealer - if they're good, will check the "paddles" where these plunger switches rest on, and adjust if needed and verify the operation.
This way, then the Dealer will have to correct the condition, and stand behind their work.