What can happen in your config file is having a path to a variable that goes through multiple sections.
Example Config
admins:
first-tier: "Kerooker"
second-tier: "Mordekaiser"
third-tier: "Yesh4"
The name "Kerooker" is from section "first-tier", which is from section "admins". To access the inner paths of our file, we use a simple '.' as a way of saying that we want the next section. So, for us to access "Kerooker", we go:
config.getString("admins.first-tier");