My name is ***** ***** I am a NSW Solicitor. Thank you for your question, and will do my best to assist you with your question. Please understand this is not legal advise but a guide to assist you.
The only thing you can do is to take them to NCAT and seek an order that the fence be removed.
If you have evidence that the council has requested it be taken down, this will assist you.
You should send a letter to the neighbour confirming you do not agree to the hight increase and request it be removed.
You need evidence of what you do.
If they do not comply then you take them to court NCAT
This is the only option you have.
If the fence is not really required and it does not comply with the act you possibly have a good course of action.
I hope this makes sense and is of assistance. If there is nothing further
thank you for using my services.
If I have missed anything, or you have any further questions please let me know
If there is anything else in the future please do not hesitate to ask.
Please do not forget to leave positive feedback.