Ridiculously poor quality of service from a premium band

Seriously disappointed with ridiculously poor quality of service from a premium brand. Most other businesses I purchase online through offer much better feedback, and much faster delivery times. The iStore online system does not allow for efficient tracking of a purchase. Their whatsapp line goes unanswered. I called them on *** yesterday and was assured that the phone I purchased would be given to couriers this morning. Now I called again around 15:30 and am told that the invoice has not been processed yet, and that delivery will occur in another 2 business days at the earliest, but by then it will be too late for my purposes. No possibility exists to escalate the matter, speak to a manager, or even to collect the device in person.