Network-Manager cant connect with openconnect VPN ("No agents were available for this request")

[Cesar Morel]

Since one of my notebooks upgrade network-manager-gnome to 0ubuntu0.16.04.4+elementary2~ubuntu0.4.1.1 when I try to connect to VPN from wingpanel applet or Network-manager editor I receive this error in logs:

Nov 19 10:39:16 mysterion NetworkManager[853]: <info> [1511098756.9639] audit: op="connection-activate" uuid="a801a3d9-5d29-430d-a16d-e82ad41ce922" name="Conexión VPN 1" pid=1670 uid=1000 result="success"
Nov 19 10:39:16 mysterion NetworkManager[853]: <info> [1511098756.9759] vpn-connection[0x1bd73e0,a801a3d9-5d29-430d-a16d-e82ad41ce922,"Conexión VPN 1",0]: Started the VPN service, PID 7066
Nov 19 10:39:17 mysterion NetworkManager[853]: <info> [1511098757.0079] vpn-connection[0x1bd73e0,a801a3d9-5d29-430d-a16d-e82ad41ce922,"Conexión VPN 1",0]: Saw the service appear; activating connection
Nov 19 10:39:17 mysterion NetworkManager[853]: <error> [1511098757.0513] vpn-connection[0x1bd73e0,a801a3d9-5d29-430d-a16d-e82ad41ce922,"Conexión VPN 1",0]: Failed to request VPN secrets #3: No agents were available for this request.

In another notebook I hold that package on 0ubuntu0.16.04.3+elementary2~ubuntu0.4.1.1 and it works fine.

In both devices I can connect from console running '$ openconnect <host>'.

As a workaround I tried to downgrade but it fails:

$ sudo apt-get install network-manager-gnome=1.2.6-0ubuntu0.16.04.3+elementary2~ubuntu0.4.1.1
Leyendo lista de paquetes... Hecho
Creando árbol de dependencias
Leyendo la información de estado... Hecho
E: No se encontró la versión «1.2.6-0ubuntu0.16.04.3+elementary2~ubuntu0.4.1.1» para «network-manager-gnome»