Washer fluid tank filled with orange stuff dealer won't cover repair!

[michaelalex17]

Hello I picked up a cpo 2015 M3 and I noticed that the washer fluid light was on. I filled the tank up with the blue fluid and the light was still on. I brought the car to the dealer and they said that it was filled with the orange fluid and it needs a new tank because the orange fluid breaks the sensor. I didn't fill it with orange stuff it must have been the previous owner, but even if I did it doesn't say anywhere that I can't fill up with the orange stuff. Should this be covered or am I missing something? Thank you

[Professor///M]

Take it to a different dealer. It's CPO, the tank should work