Annoyed client

I purchased a Smok Rigel and Juice from TVJB Ottery. I did not receive an invoice nor my points for the sale. When I emailed them, they said they would send me the invoice and make sure I would receive my points. It has been three weeks and still nothing. Why is it so easy for companies to take your money but the after sales suck. Apparently the kiosk was new and their systems were not yet setup, hence no invoice for my purchase.