Amazon review: Samsung s9 ultra tablet

I ordered the item using Barclays Finance. On 2nd April, I ran into a work-related problem that jeopardised my finances, so I repeatedly cancelled the order. The system did not register, so I later contacted Amazon Customer Services to cancel. However, in the middle of this the item was dispatched and I was advised to refuse delivery. 3rd April AM the delivery arrived and was immediately refused. The Royal Mail postman registered this as 'Refused - return to sender' on the tracking. I informed Amazon that the item had been refused. 4th April Amazon informed me that the item had been delivered to me and I had signed for it. I immediately took issue with this and spent the whole morning contacting Amazon and Royal Mail. I explained to Amazon that I had CCTV of the delivery refusal. I looked at the tracking and told them it had been taken to Edinburgh, where Amazon have a warehouse. I explained I was going through a bereavement, a work dispute, and had an autistic spectrum disability, but they did not take any steps to reduce my distress and would not accept that the item had been returned, so would not cancel the order. 4th April Royal Mail sent me proof that they had delivered the item back to Amazon in Edinburgh on 4th April. I immediately provided this proof to Amazon. It still took a long time and lots of repetition to be understood. They finally, belatedly acknowledged they had the item and that a refund would be processed, but said it would take up to 7 business days and refused to update my order page with the new status. It still says the item was delivered and signed for by me. I tried to make a formal complaint and asked to do so, requesting a formal written response ideally from a UK-based team, at least half a dozen times but the offshore customer services agents were evasive and ultimately refused, even after I repeatedly asked to escalate a formal complaint in line with Amazon's Complaints Policy and requested a remedy and written apology for the unnecessary stress caused at this difficult time.