False Adverti*****t

I'm disappointed in this company for false adverti*****t, I ordered a dstv wifi that was advertised for R749 including my active dstv compact subscription the router was delivered and the wifi is working well the only problem I encountered is that I was told that I have to pay R325.67 by 7 days after receiving that router okay I did pay it it was on the 16th of September 2023 now when I check the balance for next payment it tells me that my monthly installment is R849 how come because on the advert it was R749 what's happening Multichoice!