Why did Zoffy introduce himself to Ultraman?

So I'm going back to the very beginning of Ultraman and have just finished the last episode of Man-niisan. On the part where we first see Zoffy, why did Zoffy introduce himself to Man? Shouldn't Man-niisan know who Zoffy is since they're both from Land of Ligh and Zoffy has his Star Marks which means he's probably his commander and part of the Ultra brother. It doesn't make sense in-universe.

I get why the producers wrote it they since there wasn't an ultraman before Man-niisan, just UltraQ.