Hello Vijay,
I think that you may have misunderstood. Here is the message that we send out to our students about this offer:
Once you have received your PMP credential, you must earn 60 Professional Development Units (PDUs) every 3 years. Otherwise you will lose your PMP status.
Let me help you get over 20 of these PDUs... for Free!
Every month we are giving away a one-year license of The PDU Podcast to one lucky customer. Next month it could be you! All you have to do is to either give us your honest testimonial or tell us your PMP Exam lessons learned.
So once you write your testimonial/review, then you are entered into the drawing pool. At the end of the month we draw one winner from this pool. Only the winner receives a free license to The PDU Podcast Year 1, which will earn 20 PDUs.
So all you have to do know is wait. You might be the winner at the next drawing.