And just how exactly do you know that it’s B calling you?

This is not the point. You applied for a job and you are expected to pick up the fucking phone as much as you are expected to read and reply to an email.

The only issue with this guy post is him not either leaving a message or sending a quick email saying he tried to contact them, that’s all.

So now you don’t know what number it’s from. Maybe it’s a scam

You are ludicrous.