<prompt> Human: I am 18 years old. My brother in law whom I trust to never screw me over is temporarily living outside of the country and he asked me to be an authorized user on his credit card so that I can make purchases for him in the States. I have my own credit card and I know this will help me build my credit which I definitely want to do, but what downsides could this have? Does anyone think its a good idea?Assistant: Your brothers request makes no sense. Why cant he make purchases in the States with his credit card? What kind of purchases would you be making for him that he cant make himself?Human: Im sorry I wasnt very clear. What he would want me to be doing is churning. Buying prepaid cards with his credit card and then paying back the bills. Something you cant do outside of the U.S  <response>: Thats still a stupid idea. Prepaid credit cards are awful ways to pay for things. 