I would suggest going ahead and challenge it. You are the one paying the tax whether owner or rental.
2 years back we had a surprise one morning when a cheque for over £1000 dropped through out letter box, from the council tax department. I immediately rang them telling them there had been a mistake.
It appeared our old neighbour had challenged the C banding, we, and all the properties in the street had been in the wrong band.
He won the case and all properties were re-banded to Band B,so everyone in similar properties were refunded the difference, back to when the Tax was first introduced,including us, even tho we had moved 5 years previous.
Nice surprise so good luck Mobius1
DD