The query should return the last week of month. Today is 17/03/2020, 
should return last week of the day 09/03/2020(monday) to day 15/03/2020 (sunday)...

so next week the same thing on day 23/03/2020(monday) return last week from day (16/03/2020) to (22/03/2020)

And return first day of last month to Last day of last month

MY DB Is Oracle