Q: My son in Germany has an iPhone with Wi-Fi. I tried calling the correct number—overseas, country and locality codes. When I try to call him I get a message that he is “not available for FaceTime.” That means he can’t receive I think. What am I doing wrong? - Jim A: Unfortunately, the message that a user is “Not Available for FaceTime” can several things, including an incorrect number, the user being out of appropriate…