fix(UAE): Incorrect VAT rate display in Sales Invoice (#21882)

diff --git a/erpnext/regional/united_arab_emirates/utils.py b/erpnext/regional/united_arab_emirates/utils.py
index a01c6ce..772bbf5 100644
--- a/erpnext/regional/united_arab_emirates/utils.py
+++ b/erpnext/regional/united_arab_emirates/utils.py
@@ -1,6 +1,8 @@
 from __future__ import unicode_literals
+import frappe
 from frappe.utils import flt
 from erpnext.controllers.taxes_and_totals import get_itemised_tax
+from six import iteritems
 
 def update_itemised_tax_data(doc):
 	if not doc.taxes: return
@@ -9,7 +11,14 @@
 
 	for row in doc.items:
 		tax_rate = 0.0
-		if itemised_tax.get(row.item_code):
+		item_tax_rate = frappe.parse_json(row.item_tax_rate)
+
+		# First check if tax rate is present
+		# If not then look up in item_wise_tax_detail
+		if item_tax_rate:
+			for account, rate in iteritems(item_tax_rate):
+				tax_rate += rate
+		elif itemised_tax.get(row.item_code):
 			tax_rate = sum([tax.get('tax_rate', 0) for d, tax in itemised_tax.get(row.item_code).items()])
 
 		row.tax_rate = flt(tax_rate, row.precision("tax_rate"))