Bad handling on delayed or missed parcel delivery

I purchased 3 items on Thursday September 3th 2020 and at the time 2 items were available locally and one had to come from the UK. They delivered the first 2 items that were available locally on Monday 7th at my work place although I specified in my order it had to be delivered at my house since we were working from home and nobody would be at the office but luckily the day they delivered at the office there was one of my colleague around and he notified me of the parcel. I did enquire why they could not deliver directly to my place but they would not give me an understanding answer. However I asked them not to repeat the same mistake and provided them with my phone numbers in case there were some issues. Now since last week the Wednesday (September 9th) the parcel with the third item has arrived and I was even told at some points it was out for delivery but I never received anything. I did make several calls and sent emails but they keep on telling me they will get back to me and nobody is getting back. I am growing frustrated as I was waiting for this item urgently and I have perhaps now have talked to maybe 10 agents regarding this matter but nobody gets back to me and I have to call them everyday. In my opinion nothing is done to satisfy my demands regarding my parcel because they cannot even tell me where it is and keep on telling me they will enquire with skynet which is their courier company but it seems to be a dead end as well.