To update an existing installation you need to use the .tar file not the .img file.
Thank you for your reply are you sure about what you are saying?
I used the img file to update my RPi, i thing that Libreelec Unlike Openelec uses img files to update.
also, if you are sure can you point me to the correct file the only reference i found (in the picture) is a img file (the tar file is for updates from openelec and the zip file for a fresh install)