Missing Orders

On 3 separate occasions we've had customers call up saying their payment wasn't successful and they need to call and pay which is all good. However, when we come to check the system the order number they quote is not showing anything, in the order list the order number before and after is there! It's not in Incomplete orders either (or Abandoned/Live Carts).

I don't think the customer is getting to SagePay because their is no record of successful or failed payment. Does anyone have any ideas what could be happening? CS Card v3

The log shows details of the order being placed as you can see below

Hi jacksonsnurseries,

We've dealt with similar gateway issues before.

If you want us to investigate for you please contact us direct and we can have a look for you.

This has been happening on more than one occasion now. I would say at lets thee thine in last couple of months.