Ckeditor and Ckfinder with file manager

hello to the whole community, I need help with the integration of ckfinder and CI 3.X, I have been shipwrecked on the internet between old posts and some more current ones even within the forums of this community and I still have not been able to find advice to make the ckfinder file manager, I have already managed to do the CRUD with the editor and I can even upload images and display them in the editor and in the controller view, but I can't get the filemanager to work, it always keeps loading and showing the message "please wait. "
In console it marks error 400. Someone has an idea
Thank you very much in advance

A 400 Bad Request error means that the request the client made is incorrect or corrupt, and the server can't understand it. 

The main thing to understand is that the 400 error is a client-side error. It indicates that the request the client submitted can't be processed by the server.