ERROR With Bungee! Help!

10:28:33 [SEVERE] Exception in thread "main"
10:28:33 [SEVERE] java.lang.ClassCastException: java.lang.String cannot be cast
to java.util.Map
10:28:33 [SEVERE] at net.md_5.bungee.conf.YamlConfig.getServers(YamlConfig.j
ava:175)
10:28:33 [SEVERE] at net.md_5.bungee.conf.Configuration.load(Configuration.j
ava:85)
10:28:33 [SEVERE] at net.md_5.bungee.BungeeCord.start(BungeeCord.java:228)
10:28:33 [SEVERE] at net.md_5.bungee.Bootstrap.main(Bootstrap.java:65)


What did I do wrong?...

ERROR With Bungee! Help!