Open Question: Refusal of my in door cat in my flat owned by HA.... can I fight this?

electronic door door
I have recently moved into a ground floor flat owned by the local HA. I had a cat before I moved here but left her with my parents, but my parents circumstances have now changed and they are no longer able to look after her, I contacted my HA suggesting I had her here due to the fact is an indoor cat anyways so will never be in the communal entrance/areas of my flat. Their response was: the Association’s policy is that no cats or dogs are allowed in our flats. I appreciate that your cat is house trained and has no need for the use of communal areas but the Association would not be able to make exceptions to the rule. The reasoning behind this is to prevent others in the block from believing that they too, are allowed a cat in the property which may not be house trained. Can I fight this at all, as it is not my fault that my neighbour may not be able to house-train their animals!?
dog door for wallls