what happens if i don’t pay 316$ charge

So, my friend asked to use my Uber account because he claimed he had a referral code he could use once per account. I didn’t think anything of it; I thought I could trust him. Turns out, he’s trying to do some refund scamming thing, which I don’t know about until I see him doing it. He continues and tries to say his order didn’t get there. Eventually, they say he can’t get a refund, and now it says, “This previous payment couldn’t be processed because of insufficient funds.” I kept spamming the card he used to see if it’ll work, and it doesn’t. I genuinely don’t know what to do. I’ve called and texted him; he’s not responding. Do I push for the refund? I don’t know.