over sold my item

I ordered one of the shark vacuums last week and was wondering why i have not received it looked online and it said processing. did one of those chats and was told that it oversold and my order was going to be canceled. what really makes me mad about this is that after i ordered the lady online said they still had about 300 in stock. so im confused as to why mine was canceled and two if they had ran out why didn’t they pull it off air like they usually do? so looking for new christmas present saturday before ……