Still receiving credit final demand sms from them

They are starting to send me sms's saying that they will blacklist me for an amount that I know nothing about, what they have on their website currently is not what was there before I saw the website. If I saw that it cost 395 I would have never app**** for the loan, they have billed me for something that I didn't sign for even if it was an online application I didn't sign anything,I didn't even recieve a loan yet I get billed for an amount of R578.55, years later, why didn't they send me the emails and sms after so long. This is a voidable contract as they didn't highlight the amount for make effort in their terms and conditions. They have me 24 hours to pay or else I go on itc, I need help as I am confused and troubled by this.