Fortnite Creative?

I've built a map in fortnite with my friend for 6 hours and now I want to have it but how is that or is it even that I have them in my creative world also LG Tobi

Did you build them at your island or at your friend's island? You can also choose between several islands, if you are in the island selection lobby (creative center) you come to the creative center, if you go to menu and select creative center. Memory losses can also occur, but Epic Games has also written there

I built with a friend of his island on which I do not come myself or?