codeigniter app in wordpress (subdomain) sub folder

I have a main site say www.abc.com, with htaccess for the main site

I have another domain  ww.efd.com hosted on the main site subfolder `/efd.com` (WordPress)  it has this htaccess
   

Code:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /
    RewriteRule ^index\.php$ - [L]
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule . /index.php [L]
    </IfModule>

Now I have a CodeIgniter app www.efd.com/app hosted on subdirectory of the WordPress site /app, here is the htaccess
   

Code:

<IfModule mod_rewrite.c>
    RewriteEngine off
    RewriteBase /efd.com/app
    
    RewriteCond %{REQUEST_URI} ^system.*
    RewriteRule ^(.*)$ /index.php?/$1 [L]
    
    RewriteCond %{REQUEST_URI} ^application.*
    RewriteRule ^(.*)$ /index.php?/$1 [L]
    
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^(.*)$ /index.php?/$1 [L]
    </IfModule>

here is the directory structure

Code:

/www
.file1
.file2
.etc

      /worpresssite.com     
      .file1
      .file2
      .etc
           /codeigniter
           .file1
           .file2
           .etc

when I try to access a subfolder in the app hosted under WordPress www.efd.com/app/login, I get a 404 error, but when I access www.efd.com/app the login screen of the `app` loads correctly.