Icloud does not sync across all of my devices.

I have a Macbook Pro (laptop), iPhone, iPad and a Mac desktop. They are all signed in with the same Apple id. The laptop is my primary device (the one I use most often for documents). My iCloud folder on the laptop show the correct files and folders as I want them to be, however, the iPad and iPhone file app contains no contents, the desktop's iCloud folder contains only a few of the documents that are in the laptop's iCloud folder and the iCloud folder viewed via www.icloud.com contains vastly more files and folders that the laptop (including files and folders that were long ago deleted).

I've tried turning all the devices off, resetting all the devices, and repeatedly signing off and on with all the devices. Can someone offer a useful suggestion to solve this issue?