Poor service and failure to deliver on promise has waisted my time and resources :-(

On the 19th March 2019 I went to apply for a Dell i5 laptop. I needed it as a matter of urgency and was prepared to go to any store that had it. Leonard went on to process the application without giving me the opportunity to decide if I am prepared to wait or not. Only after he did the application he told me there is nothing in stock but will request one from Mitchells plain and I will have it by Friday the 22nd March latest, fair enough. On the 25th there was no contact from Leonard, therefore I decided to go to the store only then he told me that Mitchells plain refused with their laptop and they have 3 in stock, when I inquired what time they close Leonard said at 19:00. This was around 16:30 time of rush hour traffic. I took a risk of being hijacked/smash and grab as too many cases have been reported around the area and went there, I got there at 18:04 and they already closed at 18:00 leaving me no choice but to go there again the next day. When I got there they said the 3 they have has been reserved for certain clients unless I'm prepared to wait for weeks or a month which I was not. On the 27th March I went to Kenilworth branch and they had stock available after processing my application I waited for about 3 hours and only then was I told the offer is not in their system and I they cant give it to me I will have to reapply again when the new stock is available. Then I went to a branch at Adderley where they had to process an application again for the same item as they had stock available which came as a discrepancy due to multiple applications and had to wait from what head office had to say. My question is why must I suffer due to you failing to deliver on your promise?