Cancelling an order is messing up the increment IDs

Question

Here's the scenario. For example $oldOrder has an increment ID of 100000044

if($oldOrder->canCancel()) {
            $order->cancel();   
            $order->save();
}

When I call the above, for some reason, it's messing up the increment ID, which is becoming 000000062. In addition, if I create a new order, it will have the same increment ID of the old ordder, which is 100000044, even though the increment ID is assumed to be unique.

This is causing an issue, as the increment ID might have been used in a call to the 3rd party payment gateway previously, and linked from their side to the old order, as the increment ID is supposed to be unique to each order.

Am I doing something wrong? How do I fix this? I noticed that the increment ID doesn't mess up when I manually cancel it from the admin page, instead of the php script..

I'm creating an order the following way:

    $billingAddress = $quote->getBillingAddress()->addData($billingAddress);
    $shippingAddress = $quote->getShippingAddress()->addData($shippingAddress);

    $shippingAddress->setCollectShippingRates(true)->collectShippingRates()
                    ->setShippingMethod('flatrate_flatrate')
                    ->setPaymentMethod('purchaseorder');
    $quote->setBillingAddress($billingAddress);
    $quote->setShippingAddress($shippingAddress);
    $quote->getPayment()->importData(array('method' => 'purchaseorder'));
    $quote->collectTotals()->save();
    $quote->setReservedOrderId(null);  //----This solved the increment issue.
    $quote->reserveOrderId();
    $quote->save();

    $service = Mage::getModel('sales/service_quote', $quote);
    $service->submitAll();
    $order = $service->getOrder();
    // Mage::getSingleton('checkout/session')->setOrderId($order->getId());
    //$quote->setIsActive(0)->save();
    return $order;

Answer 1

If you are creating the orders programmatically then is possible that you forgot the get a new reservedIncrementId for the quote. The quote is reserving an increment id, and later when you convert the quote to an order will use that reserved increment id, if you cancel the order but then use the same quote for a new order you need to get a new increment id.

$quote->reserveOrderId();

//code extracted from Mage_Sales_Model_Quote
public function reserveOrderId()
{
    if (!$this->getReservedOrderId()) {
        $this->setReservedOrderId($this->_getResource()->getReservedOrderId($this));
    } else {
        //checking if reserved order id was already used for some order
        //if yes reserving new one if not using old one
        if ($this->_getResource()->isOrderIncrementIdUsed($this->getReservedOrderId())) {
            $this->setReservedOrderId($this->_getResource()->getReservedOrderId($this));
        }
    }
    return $this;
}

You can try to unset the reservedIncremenId in the quote before getting a new one.