Claiming Social Security can feel like one of those financial decisions that becomes permanent the moment you make it. Maybe you claimed at 62 because you stopped working, only to land a new job six months later, or perhaps your finances improved enough that you now wish you’d allowed your benefit to grow longer. Surprisingly, Social Security offers certain retirees something resembling a do-over through a process called withdrawal of application. The catch is that the Social Security do-over rule comes with a strict time limit, a potentially expensive repayment requirement, and restrictions that make it unsuitable for plenty of retirees. If you’ve recently started benefits and are already second-guessing the decision, here’s what you should know before that window closes.