Renault Tokai - whats happening?

I don't normally write this type of thing because I am in the service industry and understand how things are not always in your control but my situation with Renault in Tokai has reached the breaking point! For a year I have been trying to get the windscreen wipers fixed on my wife's 2018 Clio 4. A simple job you would think. The first 2 visits resulted in a "could not find anything" as at that time the fault was intermittent. In September it went in again and this time the technician advised not using wiper speed 2 but needed more time to evaluate. In December I took it back again and this time they finally took to the motor out and sent away for warranty replacement. The service manager left service controller left, no feedback, no wipers, no help! I am now dealing with the Dealer Principal and have been for the last 3 days but it's not looking good. Again, no feedback! I have had to drive there twice and I will be going again today as once again - no feedback! The sad part is that I have bought 3 Clio's from them and its time to upgrade again ....