Horrible service and very bad customer service

I am deeply disturbed with the customer service that I have received from Friday (05-06-2020) being promised that my parcel will be delivered on Friday. No one came to my address. Called on Friday AGAIN asking where my parcel is. The call agent said that it will come on Saturday. NOTHING. Called on Saturday again and they promised that it will be delivered today. Called in this morning again to see what time my parcel will be delivered, all to find out that the parcel has not gone out for today's delivery as it is still in the depot??? I need this parcel today as I am not going to be anywhere close to my house/work for the next few weeks. I need this parcel today, Please! I wanted to speak to a line manager earlier on and was on hold for close to 15 minutes only for the agent to come back and say that the manager will call me back?

I am really dissatisfied and has been a massive inconvenience for me as I have had to plan my whole life around this.

Please assist as soon as possible.

Thanks in advance