Business rates/Commercial use from a council property.

Hello can someone help please?
I live in a local Authority house, I have been operating for 5 years from my home before I even did the pre-reg, I spoke to the housing officer and his assistant and they both assured me there was no issues with being a childminder as its classed as working from home. A new housing officer has been appointed and has reviewed my tenancy and says that I am in breach as I am using the property for "commercial use", the previous housing officer never wrote to confirm that it was okay and there is nothing on the file.
I have tried to explain that we don't pay business rates ect but she is having none of it she says I am in breach of my tenancy agreement (I live in the smallest LA in England, they even advertise my spaces on their website, they knew I was a childminder so I don't really understand why they are now picking up on this).
Can anyone help or point me in the right direction to find help please?