MarkoH01: I understood completely what you did. It just does not make any sense that it worked - that's all.
pferreira1983: I just followed what gogtrial34987 said in his post.
O.K. I just tried it myself :
Having my own privacy settings set to "friends only" is not just preventing others to contact me but also preventing myself from contacting others who aren't my friends.
So I finally understood why the solution suggested by gogtrial34987 worked. However the GOG logic here is completely crazy. Why should I prevent MYSELF to contact people who aren't my friends? Why do I need a mechabnism for that? I just don't contact them and that's all right - I don't need a setting that prevents me from doing that.