Hello, thank you for the question.
I am a UK qualified solicitor and happy to help.
You can complain the insurer and then escalate to the Ombudsman if the insurer decision does not help you.
In terms of liability, with it being accepted by the driver, you could try and and sue for the cost of the increased costs you face as this is a direct consequence of the accident. I am unsure if the claim has settled?. If not you have 6 years to bring the claim to the court from the date of the accident to claim the loss.
Going back to the ombudsman, they will liaise with Hastings and see if they can persuade them to agree to not charging you what they are. If that fails, this would mean you either change insurer or pay for the costs with Hastings and then sue the driver for the extra costs incurred.
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