Complaints - does anyone at Apple listen?

This is in regard to Books. Quarterly I download and pay for a devotional book. Unfortunately, twice in the last year, the devational did not appear at the beginning of a quarter. I search for the devotional but can’t find it. I’ve contacted the author, and I was told that it was submitted to Apple. They have no control over Apple actually putting it on Books.

Does anyone know where to go to actually resolve this issue?