fixed the class method that was not returning anything if there was no mothertongue

app/models/language_skill.rb

@@ -21,7 +21,6 @@ class LanguageSkill < ApplicationRecord
         .map { |key, lang| [lang, key.to_s] }.sort
     end
 
-
     def native_language
       native_languages.first || LanguageSkill.new
     end
@@ -32,7 +31,7 @@ class LanguageSkill < ApplicationRecord
     end
 
     def native_and_human_readable
-      german_first.native_languages.map(&:full_language_skills)
+      german_first.map(&:full_language_skills)
     end  
   end
 

test/system/clients_test.rb

@@ -203,7 +203,7 @@ class ClientsTest < ApplicationSystemTestCase
     create :client, language_skills: [
       create(:language_skill, language: 'DE', level: 'good'),
       create(:language_skill, language: 'IT', level: 'native_speaker'),
-      create(:language_skill, language: 'FR', level: 'fluent')
+      create(:language_skill, language: 'FR', level: 'good')
     ]
     login_as @superadmin
     visit clients_path