(bug) unable to update an event category

CHANGELOG.md

@@ -3,6 +3,7 @@
 - Improved fix_invoice_item task
 - Fix a bug: cryptic error message when failed to create a manager
 - Fix a bug: unable to restore accounting periods closed by a deleted admin
+- Fix a bug: unable to udpate an event category
 
 ## v5.6.1 2023 January 6
 

app/models/category.rb

@@ -12,17 +12,15 @@ class Category < ApplicationRecord
   after_update :update_statistic_subtype, if: :saved_change_to_name?
   after_destroy :remove_statistic_subtype
 
-
   def create_statistic_subtype
-    index = StatisticIndex.where(es_type_key: 'event')
-    StatisticSubType.create!(statistic_types: index.first.statistic_types, key: slug, label: name)
+    index = StatisticIndex.find_by(es_type_key: 'event')
+    StatisticSubType.create!(statistic_types: index.statistic_types, key: slug, label: name)
   end
 
   def update_statistic_subtype
-    index = StatisticIndex.where(es_type_key: 'event')
+    index = StatisticIndex.find_by(es_type_key: 'event')
     subtype = StatisticSubType.joins(statistic_type_sub_types: :statistic_type)
-                              .where(key: slug, statistic_types: { statistic_index_id: index.first.id })
-                              .first
+                              .find_by(key: previous_changes[:name][0], statistic_types: { statistic_index_id: index.id })
     subtype.label = name
     subtype.save!
   end