Can't repair wipers

I took my fiancés Renault Capture to Renault Kempton Park on the 7th of November 2017 because it has faulty wipers that won't go off, a Stop - Start warning and in for 15000km/1year service. It is the 10th today and they still haven't fixed the problem with the wipers. What I don't understand is how it can take certified Renault mechanics 4 days plus to figure out a problem with wipers. Either the car is just sitting there with no one working on it or their mechanics don't know what they are doing. Please advice on what to do.