Zabbix Proxy cannot be stopped

After installing update 5.4.12 via apt we have the following error:
when rebooting the system systemctl shows that there is a process which is not a child process, but is is.
See picture.
It is not possible to stop the mentioned process except by kill the process, but when restarting the service or system the message is there again.
Therefor the proxy is not cummunicating anymore with the zabbix-server.

There are no changes in the config.