Problem with web interface and file sincronization

Greetings everyone.
I have a big problem. Some days ago, we don’t know how, all the files in our directory were cancelled, so I went on the web interface to restore them. After I did that on the web interface it continues to show me the directory are empty(0 kb in the size column) but if I enter them it shows all the files in their integrity. This problem prevent us even to sincronize and download to the pc using the client.
I did the backup of all the files using the option in the web interface, so it shows that they are in the web folder, but if I try to reupload them using the client it gives me an error.
How do I do so that the files are shown as inside the directory and to sincronize them again?

I didn’t find this argument, but feel free to redirect me if there is the solution in another post.