total-nas counter overrun (uint128 needed)

there seems to be a integer overflow problem with ia_na statistics in dhcp6

            "subnet[1].total-nas": [
                [
                    -16,
                    "2022-11-30 10:54:35.870121"
                ]
            ],

this from

                        "subnet6": [
                            {
                                "id": 1,
                                "pools": [
                                    {
                                        "pool": "2001:88b:0:ff::10-2001:88b:0:ff:ffff:ffff:ffff:ffff"
                                    }
                                ],

RT #21547