diff --git a/resources/views/pages/pdfs/purchase_order_table.blade.php b/resources/views/pages/pdfs/purchase_order_table.blade.php
index e96e6116..5f62205f 100644
--- a/resources/views/pages/pdfs/purchase_order_table.blade.php
+++ b/resources/views/pages/pdfs/purchase_order_table.blade.php
@@ -18,6 +18,26 @@
         $currency_id = $transaction->owner->fix_currency_id;
     @endphp
 
+    <?php
+
+        use App\Classes\Modules\Bookings\Services\CalculatesBookingRefundAmount;
+        use App\Classes\ValueObjects\Constants\ApprovalStatus;
+        use App\Classes\ValueObjects\Constants\TransactionType;
+
+        $booking = $po_order_transaction->owner;
+        $paymentSum = $booking->transactions()
+            ->where('type', TransactionType::PAYMENT)
+            ->where('status', ApprovalStatus::COMPLETED)
+            ->get()
+            ->sum(function ($transaction) {
+                return round($transaction->amount, 2);
+            });
+
+        $refundedAmount = (App()->make(CalculatesBookingRefundAmount::class))->calculateRefundAmount($booking, $booking->fix_currency_id);
+
+        $totalPayment = $paymentSum - $refundedAmount;
+    ?>
+
     @foreach ($po_order_transaction->transactionDetails as $key => $transaction_detail)
         @php
             $exactUnitPrice = ($currency_id) === 1 ? $transaction_detail->price : bcdiv($transaction_detail->price, $transaction->currency_rate, 7);
@@ -55,9 +75,11 @@
         <td class="right">Service Charges</td>
         <?php
             $serviceCharge = $transaction->service_charge;
-            if (isset($current_paid_amount)) {
-                $refundedServiceCharge = $subtotal + $serviceCharge - $current_paid_amount;
-                $serviceCharge = $serviceCharge - $refundedServiceCharge + $voucherDiscount;
+
+            // if has payment, calculate and deduct the refund
+            if ($totalPayment) {
+                $refundedServiceCharge = $subtotal + $serviceCharge - $totalPayment;
+                $serviceCharge = $serviceCharge - $refundedServiceCharge - $voucherDiscount;
             }
         ?>
         <td class="right">{{ number_format($serviceCharge, 2) }}</td>
diff --git a/routes/web.php b/routes/web.php
index ee36a74d..4726d956 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -172,6 +172,25 @@ Route::get('/transfer/{marking}/latest/{document_type}', function ($marking, $do
     return view('pages.pdfs.' . $lowercaseDocumentType, ['transaction' => $transaction, 'po_order_transaction' => $purchaseOrder, 'supplier' => $supplier, 'voucher_redemption' => $voucherRedemption]);
 })->name('booking.details.latest_invoice');
 
+Route::get('/transfer/{marking}/preview-proforma-invoice', function ($marking) {
+    $booking= Booking::where('marking', $marking)->first();
+
+    $transaction = $booking->transactions()
+        ->where('type', TransactionType::PAYMENT)
+        ->first();
+
+    $po_order_transaction = $booking->transactions()
+        ->where('type', TransactionType::PURCHASE_ORDER)
+        ->whereIn('status', [ApprovalStatus::PENDING_VERIFICATION, ApprovalStatus::APPROVED])
+        ->first();
+
+    $proforma_transaction = $booking->transactions()->where('type', TransactionType::PROFORMA)->first();
+
+    $supplier = Company::find($transaction->receiver);
+
+    return view('pages.pdfs.proforma_invoice', ['invoice_transaction' => $proforma_transaction, 'po_order_transaction' => $po_order_transaction, 'supplier' => $supplier]);
+});
+
 Route::get('/transfer/merge/{marking}', function ($marking) {
     return view('pages.bookings.merge', ['marking' => $marking]);
 })->name('booking.merge');