As per the title the left hand side only has stopped working. First to go was the volume up, all the rest worked now they have stopped. Anyone else had this happen?

I had the same issue with my volume up and down (RR AB 2014) and ask the dealer to replace the switch - They refitted the existing one and it sorted it for around two months, now its starting to go again.

probably clock spring.

Apologies if I am being thick, but I have no idea what CLOCK SPRING means?

it is the thing on your steering column and behind your steering wheel that allows connectivity between the cars electronics and the controls on the steering wheel/horn/air bags/heated wheel/ etc etc etc. When one goes bad certain functions will go on and off, it could be as easy as removing and giving a good clean, or it may need replacement.

When you reset things and they work, then stop again... replace switches/components only to have them work for a time and then not, generally the common denominator is the clock spring. You have to remove the air bag/steering wheel and possible some steering column covers to get at it.

Thanks for explaining.