two separate reservations for one client leads to one being ignored

1. Kea reservation identifiers:

      "host-reservation-identifiers": [
        "hw-address",
        "duid"
      ],

hr in the subnet:

                "reservations": [
                    {
                        "duid": "00:03:00:01:f6:f5:f4:f3:f2:01",
                        "prefixes": [
                            "2001:db8:1:0:4000::/110"
                        ]
                    },
                    {
                        "hw-address": "f6:f5:f4:f3:f2:01",
                        "ip-addresses": [
                            "3000::3"
                        ]
                    }
                ]

both are correct, and both, if you closely, are for the same client. I would be inclined to call it misconfiguration, but kea do not check this.

Kea do not assign prefix to client that is using duid 00:03:00:01:f6:f5:f4:f3:f2:01 but if address reservation is removed, reserved prefix is assigned correctly. Changing the order of reservations in config file do not have any effect.