I've had the same issue. Sold a heavy item to a buyer in Germany (I'm in UK) in December 2024 on a buyer collect basis. Got paid. They said they would collect when in UK in April 2025.  They didn't.  Since then I've chased up buyer with no response.  In short, I got money, but buyer has not collected.  We're now in September 2025, nine months later.  I'm clear contractually where I am in UK contracts law, as succinctly spelt out by su_9724 above.  However, eBay has it's own way of doing things!  I'm reluctant to re-advertise the item, because morally it isn't mine anymore. I don't know what else I can reasonably do.  Ideally,  I'd like clear guidance from eBay, but they've  shifted all their advice giving to the eBay 'Community'!