Review on Shaluoman 2.7V 500F Farad Capacitor - High Performance Super Capacitor with Protection Board - 35X60MM by James Lesley

I would like to change my rating but I need to replace some capacitors. I was very happy at first, but there are a couple of capacitors that won't charge to 2.7V. See my photos, there are at least three of them (two on a set of 6 and one on another set of 6). I bought this item twice in the same day because my project needed two. I plan to make more projects, but don't plan on using this manufacturer unless I can figure out why some of them don't reach 2.7V. Maybe the balance board isn't working, I'm not sure. See photos.