I tried to bake Japanese bread but it kind of failed.

I followed the recipe etc. It turns out ok. But .y dough wasn't smooth or shiny or elastic it's ABIT rough. I need shape it 2 time during the proofing process took around 1 hour + I live in a hot humid country. Than final shape and let it rest for 30min to 45min. Than bake. Pre heated oven. Fresh bake bread stays soft. First day. Second day once slice and stored in a plastic container. It dried out. I did waiting for the whole loaf to cooked down. Like how the bakery make their bread so soft and fresh for days? I my dough was around 80% hydration and 20% fat butter. And sugar and eggs etc. but than if the weather gets too hot it gets mouldy real quick sometimes day 2 already mouldy. But yeah I don't know how to preserve the bread shelf life. I even brush butter on the bread once it's done. To keep it soft but the next day it's just dry. And third day mouldy. Sometime can last till fourth day. I do not know what is wrong. submitted by /u/melon_breads