What caused the windscreen washer motor to fail on my KIA Sportage?

The water windscreen wash motor failed on an under-warranty KIA Sportage, which has been fully serviced since purchase with the same garage. They claim it is dirt that has caused it and charged me £146. I feel I cannot have done anymore than keep it all serviced as stated, when I originally asked how I should have kept it clean they initially said regular servicing but when I kicked up a fuss due to them having done all the servicing they have now backtracked and said it only gets topped up and not cleaned. I'm unhappy and £146 out of pocket. Please advise what action could be taken and, if not possible, help me let other KIA users become aware of this rip-off firm.
If you let your screen wash reservoir get gunged up with slime that is not a warranty issue with any car.
Answered by Honest John on

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