They messed up my credit score, credit amount I had does not correspond with the information they submitted to Experian

They messed up my credit score, credit amount I had does not correspond with the information they submitted to Experian. They sent sms advising that I had a credit of R2120, I took sneakers that costed Slightly over R1600. I was taken aback when I checked my credit score and it showed that I used over 149% of the R1200 credit I had. I want Truworths to fix this mess