You are only checking if there is a later timestamp *for the same "mid"*.
Since the two rows have different "mid", they are not compared.
no it works -
# select m.played, m.mid, m.action, m.gid, m.uid from words_moves m where gid=10 and not exists (select 1 from words_moves x where m.gid=x.gid AND x.played > m.played); played | mid | action | gid | uid -------------------------------+-----+--------+-----+----- 2018-02-20 15:06:01.430634+01 | 216 | expire | 10 | 11 (1 row)