UPDATE not working properly on transaction precise system versioned table

create or replace table xxx (nid int, nstate int, ntype int, primary key(nid) );

alter table xxx add tx_start BIGINT UNSIGNED GENERATED ALWAYS AS ROW START INVISIBLE, add tx_end BIGINT UNSIGNED GENERATED ALWAYS AS ROW END INVISIBLE, add PERIOD FOR SYSTEM_TIME(tx_start, tx_end), add SYSTEM VERSIONING;

insert into xxx values (1,1,1);

Query OK, 1 row affected (0.003 sec)

select nid, nstate, tx_start, tx_end from xxx for system_time all where nid=1;

+-----+--------+----------+----------------------+

| nid | nstate | tx_start | tx_end               |

+-----+--------+----------+----------------------+

|   1 |      1 |   189558 | 18446744073709551615 |

+-----+--------+----------+----------------------+

1 row in set (0.000 sec)

start transaction;

Query OK, 0 rows affected (0.000 sec)

update xxx set nstate=nstate where nid=1;

Query OK, 0 rows affected (0.001 sec)

Rows matched: 1  Changed: 0  Warnings: 0

select nid, nstate, tx_start, tx_end from xxx for system_time all where nid=1;

+-----+--------+----------+----------------------+

| nid | nstate | tx_start | tx_end               |

+-----+--------+----------+----------------------+

|   1 |      1 |   189558 |               189561 |

|   1 |      1 |   189558 | 18446744073709551615 |

+-----+--------+----------+----------------------+

2 rows in set (0.001 sec)

update xxx set nstate=3 where nid=1;

ERROR 1761 (23000): Foreign key constraint for table 'xxx', record '1-18446744073709551615' would lead to a duplicate entry in table 'xxx', key 'PRIMARY'