misco.co.uk

I placed an order, modified it the next working day (as one item had been discontinued, despite being listed as in stock on the site) and then cancelled it a few hours later.
Over a month later, I received a letter from their solictor, demanding that I pay for said order! I was told by customer services that the item had been delivered and signed for at my address - but not by me - therefore I must pay for it - even though I cancelled the order in the first place. I haven't seen or heard of any package/goods/etc.
Even if it was stolen or 'conned' from the delivery man, their disgusting tactics of threatening with a solicitor leave me stunned. Surely a phone call is cheaper??