Terrible Service

Decided to give this company and chance and ordered a Christmas gift for my daughter. Paid for item and received email notification that all is good and received tracking number from courier. Only to receive an email this morning to say sorry there was an error and they dont have stock so wont be sending,

I asked for stock to be sent when new stock arrives but get ignored. Why send an email with a tracking number if you cannot even fulfil the order because you have no stock. Surely you only send a tracking number if you have actually processed an order? How was i able to place on online order and pay and then be advised days later no stock?