hmm... everything seems OK.
The only thing I can think of is the collections page might not be optimized for any keyword, or it could also be that your site's overall authority is low (which, at 25 DA is kind of low if the sites ranking in top 10 have way more authority than you)
Also, DA is not very reliable, especially when it's so low. If it was DA 70+ we could have drawn some conclusions, but you can get to DA 50 pretty fast and easy with just a few redirects. So, use DR next time as it's a bit more reliable...
But yeah, now that I think about it, DA 25 is pretty weak, I think that is your main issue in general... Point 10-20 quality (PBN / niche edit) links to your homepage with branded anchors and I think your pages will get a ranking boost