The answer to your question depends entirely on the terms and content of the agreement. As a general rule, death of a party to a contract excuses performance. However, some contracts contain language allowing for the contract to be performed/enforced by the heirs or assigns of the decedent.
Re-read the terms of your contract. If you are confused about the sum and substance of your agreement, consult with an attorney.
Like so many things in the law there is not one simple answer to your questions. However as a starting point the answer is no - death doesn't void the contract. However impossibility of performance will excuse the impossible performance and it is likely (but not inevitable) that death will make one party's performance impossible. That is not a universal result. If the contract requires the payment of money or delivery of goods there is no per se reason why that performance (or damages for non performance) is not the obligation of the estate of the deceased party. But there may be a reason such as a provision in the contract (if it is written) dealing with the consequences of death.
I could go on infinitely about the possible scenarios that could arise here. The answer is always going to be fact specific. If you have a real legal issue and want specific advice, I would be please to have a confidential consultation with you, without any obligation.
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The above attorneys are correct. I would review the terms and contact a local contract attorney.
You should retain an attorney to address this issue. The above answer is for informational purposes only and does not constitute legal advice. I have provided this answer only based on the information presented in the question. The specific actions or answers to this issue require additional information. The above information and answering this question does not constitute an attorney-client privilege. I am not responsible for any issues, problems or losses from any reliance on this answer and information, and the consequences of such reliance.