Am I accountable for anything if someone who borrowed money in my name does not repay it, even though the debt is theirs and not mine?

If you take out a loan in your name for another person to benefit from, you are legally responsible for its repayment. If you know that the borrower will not repay it, do not help him; because he is an oppressor and an aggressor, exposed to the punishment mentioned in the Hadith: "Whoever takes people's money with the intention of repaying it, Allah will repay it on his behalf; and whoever takes it with the intention of destroying it, Allah will destroy him." It is permissible for you to intend to repay it on his behalf if he refuses, and in doing so, you would be doing good to him.