In this case, this is the problem. But they are happy with my performance. So I'm not that worried.
Since I'm confident, dominant and lacking of social phobias people tend to, (falsely) assume I know everything. As they are in this job now. When I turn out to have been honest about my abilities, and not falsely humble as they assumed, that is the problem.
Maybe it's just really specific. Maybe I just need beer now. It's not like I'm getting fired any time soon. Sure, alcohol doesn't solve problems. But neither does milk.