Same issue here too. It seemed to start within the last week as the previous week's items all tracked using the same Royal Mail Special Delivery service (from the same public counter) perfectly fine.

eBay staff, can you please verify and fix this on orders 16-13649-62461 and 26-13637-18147 please? Proof of delivery exists, but your system isn't showing as delivered and the live chat agents are really struggling to help.