So disappointed in @home Fourways Mall service

I bought a smeg toaster in November 2019. Now it is not working. I want to return it but I was told that I need to go get the invoice from @home Fourways Mall where I bought the toaster, since I do not have my slip. A week ago I called the store, gave them all the details they need and I was told the invoice will be emailed to me. I called again the following day telling them I’m still waiting for the email. I was then told that they still looking for it in the boxes. I was so shocked that they are looking for it manually and not searching on their system. I then decided that I’ll give them time to look for it. Today I called them again ( a week later) still no invoice. When I called today I was transferred to a lady that told me that they do not have invoices for 2019. I am angry, this means they **** to me when they said they are looking for my invoice. I need that invoice, Smeg is not cheap I need to return the toaster. I still feel that @home must make a plan especially after wasting my my time!!! I really find it difficult to believe that they do not keep records on their system in this day and age.