diff --git a/app/models/user.rb b/app/models/user.rb
index 3c5ad7cbf..a3ae29751 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -164,7 +164,7 @@ class User < ApplicationRecord
   # validates_format_of :mail, with: VALID_EMAIL_REGEX, multiline: true
   # validates_format_of :phone, with: VALID_PHONE_REGEX, multiline: true
   validate :validate_password_length
-  #validate :ID_number, with: VALID_NUMBER_REGEX
+  validates_format_of :ID_number, with: VALID_NUMBER_REGEX
 
   # validates :nickname, presence: true, length: { maximum: 10 }
   # validates :lastname, presence: true