If the car was a CPO (Certified Pre-owned) 2015 C-class then the blades should have been replaced before the car was offered for sale. If the wipers don't work (electrical problem) then they sold you an unsafe car and should fit it without charge.
Thank you. Yes the vehicle is CPO. From Mercedes Benz in Easton.
You could go to the dealer and ask for a replacement since you bought the car from them and they can do it as an extra for you, but wiper blades is something that is not covered under warranty etc. I believe wiper blades range from $30-50 on amazon or ebay, and they can put them on for free.
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