Postgresql - How to fix invalid hour in timestamp?

I have a table with a field called revtstmp of type bigint.

I tried to format this field with the following code:

  select
     to_char(to_timestamp(revtstmp/1000) AT TIME ZONE 'GMT', 'Day DD Month YYYY HH:mm:ss')
  from
     my_table

For the value 1571931942630, I expect to see Thursday 24 October 2019 15:45:42.
However, I see Thursday 24 October 2019 03:10:42

What am I missing ?

1 answer