Online order not honoured by Pick 'n Pay

I placed an order online for the Aim 55 inch smart tv with soundbar (CZ2155). The day before it was scheduled to be delivered, I received a call from the store saying that they are out of stock since the walk-in customers get preference over online customers. They then cancelled my order without my consent. This is not fair and is not stated anywhere in their T&Cs. I believe that Pick n Pay should honour my order and give me what I ordered. Had I known that walk-in customers get preference I would have visited the store myself to get what I wanted to purchase. Please make this right with me as I have been a loyal customer to you up to this point.