Hey- I’m a realtor. It sounds like this is a VA loan and that the lender the buyer has chosen doesn’t know what is going on. Your listing agent likely has a broker, if your agent can’t tell you exactly what the hang up is then I would go to their broker and have them tell you. Also, you are well within your right to cancel the contract or write up an addendum (it will need to be agreed upon by the buyers) that for every day after either the original closing or the new closing that the closing is delayed the buyers will pay $500. I would word it so that weekends and holidays are included and give a hard date not just say “closing date.” I would have my agent speak to their lender directly and then report back to me exactly what the problem is.