If the bank has opened and investigation and refuded you money then it sounds as though they are satisfied that this is a scam. Additionally, it doesn't sound like you are getting anything for you money so they are not providing a service to you for a fee, certainly one you are in receipt of at the moment. Therefore one a few different legal grounds I would advice that you are not liable. I would send them a message back stating that you know it is a scam and if they continue to pursue you then you will pursue legal action. Secondly, contractually if you are not receiving any service for your money then they are not holding up their end of a contractual agreement and you have the right to cancel the "contract" or "agreement". Finally, if this is a scam then you cannot pursue someone or find them liable for any payments when you have defrauded them in the first instance. Therefor I would not agree that you are liable for any such fees.
You will be relying on the laws of the Consumer Rights Act (CRA) in this matter. Firstly, as you are still in warranty then they should be fixing this for you. However, in relation to the CRA, you still have some statutory rights. If an item is no longer suitable for use then you can ask the supplier to repair or replace the item. However, as you have had it for a period of more than 6 months, the onus is one you to prove that the fault lies with the manufacturer. This can prove difficult. However, the first step of action I would recommend would be to contract the manufacturer and state that you have rights under the CRA and ask them to replace the item, additionally, I would continue to argue that you are still within warranty. If you do not get a resolution then you could raise action against them and I would make them very aware of this. However I as I stated above, you will have to show that it is the manufacturer's fault that the mattress is no longer suitable and this can be quite difficult. I would continue to purse that matter till exhaustion and hopefully knowing your rights you will be able to obtain a positive resolution.
I hope this information has helped. You can find a local solicitor who deals with this on the law society webpage which is;
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