Looks like i managed to corrupt an entire hard disk permissions. My fault.
The disk happens to be the one with all my videos collection............
Now, libreelec can read BUT not write
It looks like the problem is with entire DISK, not some directories or just some files.
I was trying via network (windows) to change permission, windows see libreelec ownership and have no authority to change permissions :
So, i guess only chance is to make things right via SSH.
I dont know much about SSH, only the basics.. so, any help is most welcomed