Delivery went missing & I got a rather short response

I ordered an item through Amazon to be delivered by City link. I tried to reschedule a delivery. Their phone system is all automatic and to get to speak to a human being is almost impossible. I rescheduled a delivery for the 22nd of August. I took a day off work and waited for it. I called at 14pm and they said it had disappeared. Just gone missing! they took my details and said they would call back. They didn't. When I called them at 1930 the staff member said the package had been found earlier at 650pm and that I could either pick it up from the depot myself or they could redeliver on Tuesday. I said neither was an option. I felt not understood. When I tried to set a new delivery date for the following Saturday I was told something about the package being delivered on Tuesday but then taken back to the depot and redelivered on Saturday if I called to redeliver. It all sounded too complicated, so I have contacted the vendor for them to arrange it directly. One of the worst experiences I have had with a delivery service.