why this one not working

Hi Mustafa!
Thanks for reaching out.

You should remove the whitespace at the beginning of the first name and use Markovitch instead of Markowitch. Your query should be:

SELECT 
    m.title, d.hire_date, d.first_name, d.last_name
FROM
    titles m
        JOIN
    employees d ON m.emp_no = d.emp_no
WHERE
    d.first_name = 'Margareta'
        AND d.last_name = 'Markovitch';

Hope this helps.
Best,
Tsvetelin