hello!

can somebody tell me the meaning of this term?

thank you very much!

 it depends on the context .

General meaning of the verb " Muhatap olmak " is " To have a question directed to oneself"

but in your case;

muhatap ol + ma [ i take this suffix as negatif ending] =  do not talk to me , him,her

1. do not talk with someone

 Benimle muhatap olma = Do not talk to me.

 Onunla muhatap olma = Do not talk to him/her.

 Bizimle muhatap olma = Do not talk to us.

 Onlara muhatap olma = Do not talk to them.

2. do not adress to someone

  Benimle muhatap olma = Dont adress to me.

The word " muhatap " is arabic origin word, "hitap = adress, hitap etmek = to adress to somebody " " muhatap= the person who is adressed"

saygilarimla!

Agree

It is also used as in being a "contact person" i.e. the person in an office that is your contact for answering questions etc.

Exactly. For example you may tell someone that he must contact only to you:

Bu iş için benimle muhatap olacaksınız, başkasıyla değil.

You will contact me (talk to me only) about/for this job, not another person. 

If "muhatap olma" is picked from a dialog box or so, the following options must be considered:

a) benimle muhatap olma = I don´t want you to talk to me 

b) onunla muhatap olma = don´t talk to him/her = ignore him/her