diff --git a/lib/devise_two_factor/models/two_factor_backupable.rb b/lib/devise_two_factor/models/two_factor_backupable.rb
index 02158bc..ecf9d13 100644
--- a/lib/devise_two_factor/models/two_factor_backupable.rb
+++ b/lib/devise_two_factor/models/two_factor_backupable.rb
@@ -30,7 +30,7 @@ def generate_otp_backup_codes!
       end
 
       # Returns true and invalidates the given code
-      # iff that code is a valid backup code.
+      # if that code is a valid backup code.
       def invalidate_otp_backup_code!(code)
         codes = self.otp_backup_codes || []