Buyer claims card was not delivered.

This is a weird one. Buyer bought two cards on two different transactions, one $5 and one $9. I sent a refund on the shipping of the $9 and shipped both in same envelope with eBay standard. Tracking on card I purchased the label from updated delivered and card I manually added the tracking shows never shipped but when clicking on the tracking number for more details it shows delivered as well. eBay does not recognize this as delivered so I’m wondering if I update tracking if it will count as a delivered card. Obviously this buyer is being opportunistic and claiming the card was never shipped because they saw that the tracking was updated. Not sure what to do in this case.