Issue Access denied for anon_ftp folder

[Avaneesh b]

I have setup anonymous ftp account for my website in plesk and it's working correctly. I also have the full permission for my ftp account which has access to the root of the webspace. When i upload/create the file to anon_ftp folder in my main ftp account i get the "550 Access is denied." error in ftp client. I only get this error for anon_ftp folder, even i can do any changes to the files inside child folders of anon_ftp. I only have the problem inside the anon_ftp.

Is the files inside anon_ftp is read only for ftp?