Renew SSL Certificate inside Keycloak Docker Container - still using old certificates

I setup a keycloak container from this manual: Docker Hub

It worked like a charm until the SSL run outdated. The files are located inside the container under the following path: etc/x509/https

I thought it would be possible updating the SSL-Certificates just by copying them over

The tls files are bind to Volumes:

"Type": "bind",
            "Source": "/home/cert/keycloak.key",
            "Destination": "/etc/x509/https/tls.key",

I copied the files to the folder /home/cert and replaced the original ones. After that i restarted the container but when accessing the homepage it still shows the “old” outdated cert.

I also run the recommended script:

sudo docker exec -it keycloak /bin/bash
cd /opt/jboss/tools/
bash x509.sh

Which returned

Creating HTTPS keystore via OpenShift's service serving x509 certificate secrets..
HTTPS keystore successfully created at: /opt/jboss/keycloak/standalone/configuration/keystores/https-keystore.jks

After that I restarted the container and still using the old certificates…

Can anyone help me?