Solid Web File Manager - problems in uploading

Hi everyone! I'm talking about solidweb.org

From about a week I found in uploading files of every dimension and type (but always under 65 MB), either in the public or in the private storage, the following error: ‘Error: Error: Web error: 413 on PUT of ’. Is that for now a general issue for the file manager platform or only mine? How can I solve? Thanks in advance.