Creditor waving off the debt

I want to ask a question about qarz. Once when I was younger like 10 years old, I asked my friend for some money and he gave it but today I heard if you don't pay back the money, you are in trouble with Allah Ta'ala and are going to get punished after death but I am pretty sure that friend said he doesn't need the money and I don't have to repay him because he's my friend so do I still have to pay him his money back? It was like 1 pound only.