I am using “velserv”, is that yours? That and the Velbus binding “created by Cedric Boon”.
I have already had really useful help by @MDAR, resolving several problems, such as:
https://forumtest.velbus.eu/t/how-to-install-and-run-velserv-a-velbus-tcp-gateway/15422
https://forumtest.velbus.eu/t/openhab-serial-port-write-error/15765
https://forumtest.velbus.eu/t/velbus-binding-for-openhab/14992
https://forumtest.velbus.eu/t/openhab-on-raspberry-pi-syncing-time-date-on-velbus-bus/15190
Bernd