Bit of a “Time is of the essence” problem…I do not give legal advice…never went to law school.
you will probably need to consult with an attorney. Without seeing the documents, confirming that all parties have in fact agreed, executed properly, within the time allocated, etc…it is almost impossible to say what can or cannot happen.
What is the law regarding purchasing a condo in New Hampshire? For instance if an offer was made ans accepted and all the paperwork was completed and forwarded to the seller/agent, can the seller then accept another offer from another party and ignore the original offer (with the signed agreement and downpayment)?