Seller Refusing to Close

[Carla Truss]

Due to unforeseen circumstances discovered by the lender, I as the buyer had to ask the sellers to extend our closing date to the following week from 11/15 to 11/22. Seller agreed to extend if I terminated my unilateral rights to extend. In addition to, my lender got the loan approved in the next 3 business days, way ahead of the financial contingency expiration date.  I granted the sellers their ask and now we are waiting for them to sign. It’s been a couple of days and they are super quiet. If they don't sign although they set forth the terms and conditions of what was needed to sign, are they in breach of contract? This has been one long unnecessary process.