select date between - PostgreSQL 9.5

Hi guys,

I got the following column:

modified_date TIMESTAMP(6) WITHOUT TIME ZONE DEFAULT
> "statement_timestamp"(),

I want to select all rows that have been modified from now to 4 months ago.

I've used these queries:

select
> modified_date,
> from
> clients
> WHERE
> modified_date BETWEEN '2016-06-13' AND '2016-09-13'

and

> select
> modified_date,
> from
> clients
> WHERE
> modified_date >='2016-06-13' AND modified_date < '2016-09-13'

But it didn't work... it returns 0 rows.... but there are rows to be shown:

select modified_date from clients ORDER BY modified_date ASC

modified_date
> -------------------
> 2015-07-11 17:23:40
> 2016-09-13 20:00:51
> 2016-09-13 20:00:51
> 2016-09-13 20:00:51
> 2016-09-13 20:00:51

What am I doing wrong?
Cheers
Patrick