Website showing 403 error

I wasn't able to access my dashboard but after recovering my the account, now, once again, I can access my dashboard but I cannot upload anything (I can't even install the WordPress)

When I try to upload files via the File Management the following error shows up

"Cannot access your files, it could be a temporary problem due to an update or technical failure. In this case, if the problem persists for more than two hours, notify it on the forum."

When I try to install Wordpress this one shows up "Error Installation failed/
Cannot copy files in user's space"

Also, I tried to upload files via FTP but nothing changes. Well, the only file I can see through the FTP is the .ftpquota. but I tried to upload an index.html, a .htaccess file, change the files permissions but nothing has changed.

There is something I/You can do to solve this problem. I was about to delete this account but I can't create another one because your registration page isn't working.

Please contact our Abuse department providing the details of the issue.