Error: the live system creation is aborted! An error occurred while creating the container file.

I am using Ubuntu 18.04.3 Desktop in a virtual machine (VirtualBox)

I am trying to make a live system creation with systemback. Everything goes smoothly, the three main processes execute for a while and then at the end of the third process when it's supposed to finish, I get a window saying: the live system creation is aborted! An error occurred while creating the container file.

To get systemback on this version of Ubuntu, I did terminal command:

sudo add-apt-repository "deb http://ppa.launchpad.net/nemh/systemback/ubuntu xenial main"
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 38203C2C8B7B4AB813E915B14E4942973C62A1B
sudo apt install systemback

I tried making the output directory a USB drive and the /home directory
I tried updating systemback with sudo 'apt update'

below is my terminal output :

user@DF-VirtualBox:~$ sudo apt update
Hit:1 http://us.archive.ubuntu.com/ubuntu bionic InRelease
Get:2 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]
Get:3 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB]
Get:4 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]
Hit:5 http://ppa.launchpad.net/nemh/systemback/ubuntu xenial InRelease
Hit:6 http://ppa.launchpad.net/cubic-wizard/release/ubuntu bionic InRelease
Ign:7 http://ppa.launchpad.net/nemh/systemback/ubuntu bionic InRelease
Get:8 http://us.archive.ubuntu.com/ubuntu bionic-updates/main i386 Packages [625 kB]
Err:9 http://ppa.launchpad.net/nemh/systemback/ubuntu bionic Release
  404 Not Found [IP: 91.189.95.83 80]
Get:10 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages [817 kB]
Get:11 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 DEP-11 Metadata [295 kB]
Get:12 http://us.archive.ubuntu.com/ubuntu bionic-updates/main DEP-11 48x48 Icons [72.3 kB]
Get:13 http://us.archive.ubuntu.com/ubuntu bionic-updates/main DEP-11 64x64 Icons [143 kB]
Get:14 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 Packages [1,033 kB]
Get:15 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe i386 Packages [997 kB]
Get:16 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 DEP-11 Metadata [264 kB]
Get:17 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe DEP-11 48x48 Icons [202 kB]
Get:18 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe DEP-11 64x64 Icons [452 kB]
Get:19 http://us.archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 DEP-11 Metadata [2,464 B]
Get:20 http://us.archive.ubuntu.com/ubuntu bionic-backports/universe amd64 DEP-11 Metadata [7,976 B]
Get:21 http://security.ubuntu.com/ubuntu bionic-security/main amd64 DEP-11 Metadata [38.5 kB]
Get:22 http://security.ubuntu.com/ubuntu bionic-security/main DEP-11 48x48 Icons [17.6 kB]
Get:23 http://security.ubuntu.com/ubuntu bionic-security/main DEP-11 64x64 Icons [41.5 kB]
Get:24 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 DEP-11 Metadata [42.0 kB]
Get:25 http://security.ubuntu.com/ubuntu bionic-security/universe DEP-11 48x48 Icons [16.4 kB]
Get:26 http://security.ubuntu.com/ubuntu bionic-security/universe DEP-11 64x64 Icons [113 kB]
Get:27 http://security.ubuntu.com/ubuntu bionic-security/multiverse amd64 DEP-11 Metadata [2,464 B]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/nemh/systemback/ubuntu bionic Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

PLEASE HELP!

I've been at this for days. Before this I was trying LinuxLiveKit and kept having kernal problems. Now I found systemback and thought I saw the light until I ran into another speed bump!

Thank you!!!!