False advertising

I bought a 5gig data bundle for 7 days. After payment went through, i received a 4 gig bundle for 30 days which i incorrect. I tried chatting to them online, but they take roughly 20min to reply (if they reply). I then phoned them to ask what is going on with this, and the lady keeps telling me that because i bought it close to the end of the month, i will get the other 1gig on the 1ste (start of the next month). this does not make sense in anyway or form. payed for a specific product, and received something completely different. It like buying a porche and they give you a hilux.