Renaming States

I am having trouble with renaming states in the state_names_l_english.yml file, it used to work just fine but after No step back, By blood alone and Arms against tyranny it doesn't work anymore for some reason. The file looks like this:

l_english:

 STATE_58: "Burdaard"

 STATE_59: "Hegebeintum"

Now renaming state 58 (Schleswig - Holstein) to Burdaard works just fine, but renaming state 59 (Ost - Hannover) to Hegebeintum does not work for some reason and when I rename 59 to Burdaard then it does work. This makes no sense to me, does anyone know why this is?