Formal letter to an academic person holding Master's degree
Don't overthink it. Try to find out the gender and then use &quot;Mr.&quot; or &quot;Mrs.&quot;
Even many professors don't insist on titles most the time and a person with a master degree is usually just a (former) student, who is one step further than other students. In a second E-Mail you can then use how they call themself in their signature.
&quot;Dear Director&quot; may be appropriate, when the job position is relevant to your E-Mail.
(It may depend on the country how much people want to be addressed using their academic full title)