how to get vsftpd anonymous upload and download working in ubuntu

I am using ubuntu 18.04. I need to set up vsftpd in so that anonymous uploads and downloads are possible (i.e logging in by typing "anonymous" as username and anything as password). I also need the anonymous root to be a specific directory. I know it's not secure, but security doesn't matter in this case. My vsftpd.conf file:

listen=YES
local_enable=YES
write_enable=YES
xferlog_file=YES

anonymous_enable=YES
anon_root=/var/www/html/Ax78klm34e4ijKSi8lnik
anon_upload_enable=YES
anon_mkdir_write_enable=YES

chown_uploads=YES
chown_username=ftp
allow_writeable_chroot=YES

These are the permissions for that directory

drwxrwxrwx 5 root    root     4096 Jun  6 11:01 ./
drwxr-xr-x 3 root    root     4096 Jun  4 10:07 ../
drwxrwxr-x 7 root    root     4096 May 27 19:34 assets/
drwxrwxrwx 2 root    root     4096 Jun  5 22:03 Ax78klm34e4ijKSi8lnik/
-rw-r--r-- 1 root    root      465 Jun  4 16:55 config.php
-rw-rw-r-- 1 root    root      883 May 27 19:34 gulpfile.js
-rw-rw-r-- 1 root    root    57676 Jun  5 14:32 index.php
-rw-rw-r-- 1 root    root     1069 May 27 19:34 LICENSE
-rw-r--r-- 1 root    root     3291 Jun  5 17:48 login.php
drwxrwxr-x 2 root    root     4096 May 27 19:34 media/
-rw-rw-r-- 1 root    root     1296 Jun  5 11:45 package.json
-rw-r--r-- 1 root    root     5307 Jun  4 23:36 register.php
-rw-r--r-- 1 root    root       31 Jun  5 14:40 robots.txt
-rw-r--r-- 1 root    root      109 Jun  5 17:43 test.php

This is the error that i'm getting

Connected to 192.168.43.57.
220 (vsFTPd 3.0.3)
Name (192.168.43.57:archangel): anonymous
331 Please specify the password.
Password:
500 OOPS: vsftpd: refusing to run with writable root inside chroot()
Login failed.
ftp> 

I tried changing the permissions of the required directory to 0755, then the above issue is resolved, but i'm unable to upload in that case.