iPad storage full message

About a month ago, I started getting storage full messages on my 16Gb iPad. I researched this (a little), pared down my apps, and followed most of the steps outlined in the main thread to this question. I’ve never been big with photos and I delete my emails several times a day, so I don’t think those are problem areas. I’ve kept my storage down around 10 gigs for weeks now, but the warning in Settings has never gone away. I installed a cleaner which claimed it cleaned this up, but again, the Settings warning was unchanged. As I understand it, iOS takes up 8-9 gigs. I’ve pared my apps down to things I use every day. What more can I do? Most of what I use is story based, Kindle, The Athletic, Bleacher Report, ComiXology. All of those fluctuate quite a bit in their storage requirements. I am on Facebook and it’s a bit of a pig, but not horrible. Any suggestions, (preferably something I haven’t already tried)?