Music rights are very complex. Even royalty free and “copyright free” music can come with limitations on how it can be used. The safest path is to use original music you have created yourself or that you fully own the rights to. If you are using music that you have created or own outright and your island is still getting rejected because of it, please surface the issue through player support so we can address it. We are actively exploring ways to enable more music in our ecosystem.