500 OOPS: cannot change directory:/home/username

ftp error : 500 OOPS: cannot change directory:/home/username

Solution I : 
Disable SELinux. To see, how to disable it, Click here.

Solution II :
If you do not want to disable SELinux. Follow this.
Check directory status.

$ getsebool -a | grep ftp

If ftp_home_dir is set to off, the error can be there, we need to make this attribute on using

$ setsebool -P ftp_home_dir on

Now restart vsftpd and try to reconnect again.
or

$ setsebool -P ftp_home_dir=1

Now restart vsftpd and try to reconnect again.

If you are still facing error, check the username directory inside /home directory.
The username directory should be there to log in to the ftp account.