We have a an American neighbor 55 years old, living on his own right next door (apartment). right now i am pretty scared because i haven't seen him today last time i saw him was like 20 hours ago, I know he didn't leave because his bike was still on the garage he always ride with his bike when he leaves. We talked everyday since his next door we're like friends he talks about anything and he would tell if he's going to somewhere, but this time 'nothing'... I'm pretty scared if his doing okay. This is the first time I haven't saw him for a day without having a hint if his up to somewhere. I knocked his door many times today if he was inside but no response unfortunately... Is there anything I can do????