Has it been 4 full days since you opened it? If so close it-they get a strike-you get your FVF's back and are free to relist.
Add them to your BBL too:
Make sure that it has been at least 96 hours since you opened the unpaid item case. You will only see the correct option to use to close the case after this time has passed. If you close the case early, you will not get your final value fees back and the buyer will not get a UPI strike on their account.
If your buyer hasn't paid you by now, they're not going to. Just close the case, get your fees back and relist the item for someone who does want to pay for it.