Cached plugins not working (cache not written)

Troubleshooting
4

I actually see some errors running service xinetd status:

Oct 19 07:47:02 web08 xinetd[4889]: bind retry attempt 9
Oct 19 07:47:02 web08 xinetd[4889]: bind failed (Address already in use (errno = 98)). service = check_mk
Oct 19 07:47:02 web08 xinetd[4889]: bind retry attempt 10
Oct 19 07:47:02 web08 xinetd[4889]: bind failed (Address already in use (errno = 98)). service = check_mk

EDIT: It looks there is systemd listening on 6556

tcp6 0 0 :::6556 :::* LISTEN 1/systemd

systemctl list-sockets:

[::]:6556 check_mk.socket check_mk@188662-37.187.135.204:6556-51.15.138.178:33766.service