The PL-200 exam is a specialty certification and previously, Microsoft's role-based and specialty certifications expired after two years. You would then have to retake the exam(s) to get recertified. But things have changed.
Starting in June 2021, Microsoft changed that role-based and specialty certifications are valid for one year, but they can be renewed online for free. The renewal window begins six months before the certification expires and during this time before the certification expires, you can take a free online assessment.
So no matter when you renew your certification within the six-month renewal window, the certification validity will be extended one year from its initial expiration. (For example, if you earned your certification like me in December 2021 and you passed your free renewal assessment in July 2022 (at the very beginning of your renewal window) your certification would now be valid until December 2023.
The other great news is that you can retake your assessment as many times as you need to pass. You just have to pass it before your certification expires. But don't let your certification expire, because once its expired you need to sit the certification exam again.