If your score is far from the Harvard Duolingo English Test score requirement, retaking it is your best choice. However, if you do this, make sure you spend a lot of time sharpening your shortcomings and working out how to enhance your score. The more points you need to meet the Harvard DET score requirement, the more studying time you'll need. And the more hours you need to study, the more time you should strive to set aside before the exam. It's advisable to give yourself at least three to six months to prepare for the Duolingo English Test.