Can't connect to VPN L2TP from Ubuntu 18.04 CLI

I have a VPN that is working when I connect through my windows using L2TP, however when I set up my ubuntu with CLI its not working. I get the following error when I run

$ nmcli c up myvpn

Error output

Error: Connection activation failed: Could not find source connection.

## What I've tried - disabled the firewall sudo ufw disable - created the vpn configuration with

nmcli connection add connection.id myvpn con-name myvpn type VPN vpn-type l2tp ifname -- connection.autoconnect no ipv4.method auto vpn.data "gateway = x.x.x.x, ipsec-enabled = yes, ipsec-psk = 0s"$(base64 <<<'psk***psk' | rev | cut -c2- | rev)"=, mru = 1400, mtu = 1400, password-flags = 0, refuse-chap = yes, refuse-mschap = yes, refuse-pap = yes, require-mppe = yes, user = username" vpn.secrets password=mypassword

- NetworkManager is managing the following interfaces

user@ubunut:~# nmcli device status
DEVICE   TYPE      STATE      CONNECTION
eth0     ethernet  connected  eth0
docker0  bridge    connected  docker0
lo       loopback  unmanaged  --

- list all NM connections: nmcli con

NAME             UUID                     TYPE      DEVICE
docker0          ef3eb3a8-c46e-434c-bfcb  bridge    docker0
eth0             fc920355-d18e-495a-b3ca  ethernet  eth0
myvpn	         2b24ce55-98d3-4bc0-8b52  vpn       --
Ifupdown (eth0)  681b428f-beaf-8932-dce4  ethernet  --

Still I'm not able to connect and I'm stuck now. I don't know what else to do to make it work. Does anyone have any idea what the problem might be?