On Ubuntu 1.3.16 ... 1.3.18 breaks VPN connection

[robertgalambos]

L2TP VPN is used in my company. I am using Ubunut 22.04 LTS. It broke after upgrading to 22.04 before it was working.
Despite all the searching on the internet, and in this issue list but It will not work... I need to use a Raspbian where there are different (older) packages to be able to connect to the VPN. I use fully the same config on both.

I use the "network-manager-l2tp network-manager-l2tp-gnome xl2tpd"
The stack says it is connected to the VPN...but nothing is reachable, and after a while it says the VPN terminated.

Everything seems to be OK in the log...the only thing that pops up during this looks like this:

Sep 22 21:56:04 cube charon: 11[ENC] parsed INFORMATIONAL_V1 request 3193364741 [ HASH N(DPD) ]
Sep 22 21:56:04 cube charon: 11[ENC] generating INFORMATIONAL_V1 request 1901276591 [ HASH N(DPD_ACK) ]
Sep 22 21:56:04 cube charon: 11[NET] sending packet: from 46.107.37.94[500] to 77.221.39.74[500] (92 bytes)
Sep 22 21:56:06 cube NetworkManager[5320]: xl2tpd[5320]: check_control: Received out of order control packet on tunnel 26736 (got 3, expected 4)
Sep 22 21:56:06 cube NetworkManager[5320]: xl2tpd[5320]: handle_control: bad control packet!
Sep 22 21:56:08 cube NetworkManager[5320]: xl2tpd[5320]: check_control: Received out of order control packet on tunnel 26736 (got 3, expected 4)
Sep 22 21:56:08 cube NetworkManager[5320]: xl2tpd[5320]: handle_control: bad control packet!
Sep 22 21:56:12 cube NetworkManager[5320]: xl2tpd[5320]: check_control: Received out of order control packet on tunnel 26736 (got 3, expected 4)
Sep 22 21:56:12 cube NetworkManager[5320]: xl2tpd[5320]: handle_control: bad control packet!
Sep 22 21:56:20 cube NetworkManager[5320]: xl2tpd[5320]: check_control: Received out of order control packet on tunnel 26736 (got 3, expected 4)
Sep 22 21:56:20 cube NetworkManager[5320]: xl2tpd[5320]: handle_control: bad control packet!
Sep 22 21:56:25 cube charon: 15[NET] received packet: from 77.221.39.74[500] to 46.107.37.94[500] (84 bytes)
Sep 22 21:56:25 cube charon: 15[ENC] parsed INFORMATIONAL_V1 request 1712813217 [ HASH D ]
Sep 22 21:56:25 cube charon: 15[IKE] received DELETE for IKE_SA 16c4eac1-a002-4197-a3d5-87e8c196e80e[1]
Sep 22 21:56:25 cube charon: 15[IKE] deleting IKE_SA 16c4eac1-a002-4197-a3d5-87e8c196e80e[1] between 46.107.37.94[46.107.37.94]...77.221.39.74[77.221.39.74]
Sep 22 21:56:31 cube NetworkManager[5320]: xl2tpd[5320]: Maximum retries exceeded for tunnel 24135.  Closing.
Sep 22 21:56:31 cube NetworkManager[5320]: xl2tpd[5320]: Terminating pppd: sending TERM signal to pid 5321
Sep 22 21:56:31 cube NetworkManager[5320]: xl2tpd[5320]: Connection 26736 closed to 77.221.39.74, port 1701 (Timeout)
Sep 22 21:56:31 cube NetworkManager[1076]: <info>  [1695412591.1090] device (ppp0): state change: disconnected -> unmanaged (reason 'connection-assumed', sys-iface-state: 'external')
Sep 22 21:56:31 cube pppd[5321]: Terminating on signal 15
Sep 22 21:56:31 cube pppd[5321]: Connect time 1.3 minutes.
Sep 22 21:56:31 cube pppd[5321]: Sent 503525 bytes, received 0 bytes.
Sep 22 21:56:31 cube charon: 08[KNL] interface ppp0 deactivated
Sep 22 21:56:31 cube charon: 10[KNL] 192.168.252.100 disappeared from ppp0
Sep 22 21:56:31 cube pppd[5321]: Overriding mtu 1500 to 1400
Sep 22 21:56:31 cube pppd[5321]: Overriding mru 1500 to mtu value 1400
Sep 22 21:56:37 cube pppd[5321]: Connection terminated.
Sep 22 21:56:37 cube charon: 06[KNL] interface ppp0 deleted

Is there any information how to solve this problem?
Thanks in advance.

[wp1411847064]

Change Makefile

[robertgalambos]

How?