Since you paid for your own course, then it is completely up to you if you want to earn Certification or not. There is no requirement that you earn a certain score in order to move on in the course or take other courses.
The only exception to this, as you’ve seen, is Part 1 of the Final exam. We do have that set to block someone from taking Part 2 if they didn’t get 90% on Part 1. That’s just because most students are aiming for Certification, and we want to make sure they understand the questions and answers on Part 1 before doing the open answer final.
As a reminder, the requirements for Certification are 80% or higher on each unit quiz, and 90% or higher on each exam. I think your scores (except for the Final) meet that criteria, unless I missed something when I glanced over your results.
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