Cold feet - no heat in footwell

[stillstanding]

2012 Passat DRG 2.0 with manual heating controls.

Everything works except there is no hot (or cold air) to footwells. Screen, upper vents OK. Same problem at all fan settings etc.

I think this happened around the time a few weeks ago when the heating went crazy and wouldn't respond to the control. I had to open the windows for a few minutes until I could pull off the road and stop. Switched the ignition off, on again and temp. control was fine after that.

Any ideas?

Thanks, Mike