Repeated delivery of the wrong item, terrible courier service

Placed an order for three items on 9 Feb, one included a phone case for a Galaxy S7. They sent me the case for the S7 Edge. Went through the process to return it and have it replaced with the correct item. Received the replacement however it was, again, a case for the S7 Edge. Returned it again for a replacement and AGAIN was sent the case for the S7 Edge. On all these deliveries the courier on several occasions sent me reschedule notifications at short notice. On the last delivery the courier did not even keep to the date it rescheduled and simply pitched up late the following day.