I am unable to reach one of my faculty member through email, phone call or even in person, what may I do?
Here are some ideas (from high to low priority / potential efficacy ):


Explain administrative stuff of the faculty your situation and ask for help. Maybe they know that he/she is abroad and will come soon. Or he/she is sick and will likely not be able to help you.
Find his/her students and explain your situation and ask for help.
Talk to some other faculty member asking whether he/she can help you to locate him.