Mr-dstv.co.za charged me higher fee from quoted amount. Furthermore still waiting for my invoice.

On the 25 02 2021 I had contacted Mr dstv (www.mr-dstv.co.za) to come and assist me with a problem I was having with in regards with my DSTV decoder not receiving any signal from the dish. We communicated via WhatsApp and call and a quote was sent via WhatsApp of R350.00 3 guys arrived onsite just after 13h00. 1 got on the roof and the other was figitting with the decoder. 30minutes later they were done and it was time to pay. Then the priced charged from R350.00 to R450.00 we chatted about the indifference in price and they gave me some silly excuses that still don't make sense why I had to pay a hundred rand over the initial quotation. A payment of R450.00 was made and I had specifically mentioned that I require an invoice. I was then told they needed my email address to which it can be sent to. 24hrs later I'm still waiting. How long does it take to issue an invoice