Thank you. at the time you had agreed to hire the studio a legally binding contract would have come into operation because this is automatically formed when there is an offer by one party and an acceptance by another. So you had offered to hire the studio on a specific date and they in turn agreed to your offer and by doing so and entering into this mutual agreement a contract would have been formed. It is not a requirement to have anything signed or even in writing.
You then have to consider if the provision of the invoice was a critical part of the contract which if not undertaken, made the whole contract null and void. I am not sure how critical the provision of an invoice would have been unless you had made it specifically clear at the outset that you specifically require that urgently by a set date. So it is perhaps not possible to use that as an argument that the contract was void.
Then there was the business sale. Just because a business changes hands does not make all existing contractual obligations null and void. Your contract can transfer to the new owner as long as the service they would provide is not substantially different to that which you had initially agreed to.
Nevertheless, the lack of communication is something you may use by arguing that you had list confidence in them and that as you could not establish that the booing still stood, you would have cancelled to seek hire elsewhere.
In any event, they are requesting money from you now but you cannot be forced to pay anything. The only way for them to do so is to take you to court and this may never happen. So you can stick to the reasons for cancellation as already mentioned and can maintain you are not paying anything. It is up to them as to whether to take you to court or not – if they do you can always reconsider your position and whether to offer some kind of settlement at least.
I hope this has answered your query. I would be grateful if you could please take a second to leave a positive rating by selecting 3, 4 or 5 stars - this is an important part of our process and recognises the time I have spent assisting you. If you still need me to clarify anything else, please get back to me on here and I will assist further as best as I can. Thank you