Wired behaviour from SELECT

Two different SELECT sql statement don't behave the same way.
The below sql statement produces the right output
SELECT nickname, password FROM password WHERE id='0938105618107N1';
  nickname   | password
-------------+----------
 Piccard@@21 |  Arbol
(1 row)
However, if this sql statement produces the wrong output
SELECT nickname, password FROM password WHERE nickname='Arbol';
 nickname | password
----------+----------
(0 rows)
What am I doing wrong?