Update

app/models/sale_item.rb

@@ -39,8 +39,8 @@ class SaleItem < ApplicationRecord
       # Check for actual sale items
       sale_items.each do |si|
         if si.account_id == a.id
-          account_price[:price] = account_price[:price] + si.price          
+          account_price[:price] = account_price[:price] + si.price
-        end        
+        end
       end
       price_accounts.push(account_price)
     end
@@ -55,10 +55,10 @@ class SaleItem < ApplicationRecord
       discount_account = {:name => a.title, :price => 0}
 
       # Check for actual sale items
-      sale_items.where("is_taxable = 0 AND remark = 'Discount'").find_each do |si|
+      sale_items.where("is_taxable = false AND remark = 'Discount'").find_each do |si|
         if si.account_id == a.id
-          discount_account[:price] = (discount_account[:price] + si.price) * -1          
+          discount_account[:price] = (discount_account[:price] + si.price) * -1
-        end        
+        end
       end
       discount_accounts.push(discount_account)
     end