Possibly 'left overs' from the massive mess on everything eBay that happened for two days last week?

eBay rarely know about any issues until many people have told them (they flat out denied any issues when I contacted last week about absolutely nothing working) Even when it was on Down Detector and other sites, eBay said nope, there is no problems at all

Have you tried the 'usual' (clearing cookies/cache/tried another browser)