Troubleshooting Moby Evolution Wrap Carrier?

Earlier in my pregnancy, I got to test out a Moby Wrap at our baby care prenatal class, and I really liked it and felt it would be a really useful item to have! So when I saw that the Moby Wrap Evolution was available in a pretty floral print, I registered for it! Lo and behold, at our baby shower a couple weekends ago, someone actually purchased it for us! I was excited to try it out again, so the other day I put it on using a toy baby doll as a stand-in for my actual baby, who isn’t quite here yet. However, once everything was all wrapped, the Moby label that marks the middle of the wrap and acts as the third layer of support for baby, was loose and for the life of me, I could not get that part to tighten up enough! Like the lower part of that front panel was fine, but the upper part where the label itself is—it just keeps slipping down. I watched numerous tutorials, and of course read the instructions, but I can’t seem to fix it and I’m frustrated! Sm I doing something wrong?! Or could it just be that at 37w pregnant, it simply isn’t gonna fit as well as it will post-partum due to the giant bump I’m currently sporting?