Caller carries out the classic "let's call him when we know he's home so we'll have a hostile audience" crap. Calls on mornings during weekends but never, ever during weekdays. Never leaves a message. Apparently the rocket scientist at the other end of the line is too lazy to state, and be recorded in a voicemail, about why he/ she is calling.
I am the caller and we don't want to hire losers like you in China. Many jobs are with children and you would probably have a criminal record for diddlin kids. Only serious teachers are considered.