There is a solution with the dispute involving a council.
You should first make a complaint to the council - this is required before you can involve the Ombudsman. The complaint would be due to having been wrongly advised and due to negligence on the council's part. You can make a complaint via this link: https://hillingdon.gov.uk/complaints
If that does not resolve this, involve the Local Government Ombudsman (LGO) : https://www.lgo.org.uk/make-a-complaint
The LGO may be able to help but you would need to firstly exhaust the council's complaints procedure, unless you have done this already. The Ombudsman scheme is free of charge and quicker than court action. As it is an arbitration scheme, the Ombudsman’s decision would be binding upon the council if you accepted the decision.
If the Ombudsman does not uphold your complaint, or you disagree with their decision then there is a legal remedy available against a council with it being a public body.
You can issue "Judicial Review" proceedings which is where you involve the court, and a senior judge or panel of judges looks at the legality of a council's decision. If the judge(s) find in your favour, they will make an order which is binding on the public body (e.g. they may say the public body’s decision was invalid) and they are then forced to act to sort the problem out. Further, if your human rights were breached then compensation may also be payable.
The issue with judicial review is that the cases are quite complex, but as a result of that, a law firm can usually recover their legal costs from the council if they win the application. You should be able to have a no win no fee agreement with the law firm, to sue the council. Or if you are in receipt of means tested benefits then legal aid may well be available to you.
Here are a few firms who specialise in this area :
I hope this helps - please feel free to ask me anything else.