TFG Unable to supply goods ordered online

TFG's Black Friday promotion started early.Placed an order on 28 November only to receive an sms and email on 2 December ,to say that my order had been cancelled due to lack of stock or damaged items!! My question is ,why have the promotion if you are unable to supply enough stock? When processing my order online,nowhere did it say there wasn't stock,If this were the case,the sale would not have gone through.

I even received an Invoice to say my purchase had been approved.

Now all TFG can tell me is : "Good Day, Thank you for your enquiry regarding your most recent online purchase for order p*********9. We are very sorry to hear that we have disappointed you. Due to the popularity of this promotion your item was not available at the time of picking your parcel. The funds that were reserved for this order will be reversed to your TFG account"

Is this email supposed to make it okay ? This is false advertising!! Dont advertise if you are unable to supply your customers with what the purchase!!

I am not interested in a refund,I would like my Son's shoes that i ordered.