FTP using VSFTPD on AWS Linux returns 'Failed to retrieve directory listing' intermittently

I'm running the AWS version of Linux. I want my FTP users to only have access to their home directories and created these directories for each with the proper permissions.

Using Filezilla it works sometimes...but then other times it doesn't work. I get

Status: Connected
Status: Retrieving directory listing...
Command:    PWD
Response:   257 "/"
Command:    TYPE I
Response:   200 Switching to Binary mode.
Command:    PASV
Response:   227 Entering Passive Mode (x,x,x,x,x,x).
Command:    LIST
Error:  Connection timed out
Error:  Failed to retrieve directory listing

Using the prompt (on windows) it works every time.

Others seem to have this problem and I tried implementing some of the suggestions but the issue remains.

I added this to the VSFTPD.conf file

connect_from_port_20=YES
pasv_enable=YES
pasv_min_port=64000
pasv_max_port=64321
#port_enable=YES
pasv_address=x.x.x.x
pasv_addr_resolve=YES

Those port ranges are open on the AWS security group

Thank you