hello, hoping someone can help me

i have a Y reg KA which has been fine up until this morning when it cut out as i was driving down a hill toward a roundabout. thought it was a bit weird, but put it down to my driving
about 5 mins later it happened again as i was slowing down for a roundabout. its not stalling and jolting forward, it just cut out.

anyway this afternoon it was absolutly fine, not even a noise as i drove back from work

wondered if its anything to worry about? my bf is talking about cleaning my idle control valve?
but the car was fine on tick-over?
im on absolutly rubbish wages, and hoping its something that can be left/not too serious

any help would be fab. thanks