Daniel wishes to sell his PlayStation 5 video game console as he does not use it any more. He advertises it for sale for $600. Hamish phones and says he will buy it at that price. Daniel says that he has changed his mind about selling, but thinks that he will charge $650 for it if he decides to sell. Hamish then offers $620, but Daniel says he needs to think about it.

At the football the next day, Daniel offers Paul the PlayStation 5 for $640. When Paul says no, Daniel says he will keep the offer open for Paul for 7 days in exchange for a lift to the football next week. Paul agrees to this.

A day later, Daniel is in sudden need of money, and phones Hamish, saying that he accepts the offer of $620. Hamish says that he has changed his mind and doesn’t want to buy the console anymore.

Daniel, being concerned about the legal consequences of the situation mentioned above, seeks advice from a Generative AI system regarding its contract law implications. The AI system responds with the following advice:

‘Daniel advertised the PlayStation 5 for $600. Hamish offered $600, but Daniel countered at $650. Afterward, Hamish offered $620. Later, Daniel offered it to Paul for $640, and Paul agreed. When Daniel accepted Hamish's $620 offer, Hamish changed his mind. As a result, Daniel is obliged to sell to Paul for $640, while Hamish has no such obligation.’

Part A - Using the Generative AI produced response above, identify the elements of the IRAC method that are reflected in this response. That is, identify which sentence(s) addresses the issue, rule, application, and conclusion steps of the IRAC process.

Part B - The Generative AI response provided is incorrect and lacks identification of all legal issues. Additionally, it does not accurately apply the law to the facts. Your task is to present a clear overview of the legal situation. You are therefore required to write a new response that accurately identifies the contractual liabilities of Daniel, Hamish, and Paul. Refer to relevant sources of law (case law and/or legislation) to support your arguments. Be sure to fully explain your answer.