I had the same exact experience the last time I sold on ebay, in 2017. I sold an $800 item. One day before the claim window closed, the buyer filed a claim saying it had never arrived and claiming they emailed me several times and I never responded. I submitted proof of delivery from UPS and pointed out the simple fact that I had received no messages from the buyer through ebay messaging. Ebay gave them a full refund…
EBay in 2017 was a giant shitshow (and probably still is, but I don't use it anymore). Both their security and support are complete trash, even if you happen to be lucky (like me) and they reply quickly. I woke up one morning to get an email notification thanking me for purchasing a back bumper, a wing, and a few other parts for a 2012 Hyundai Genesis, which I obviously don't have and neither have I made that purchas…
A number of online services I use send SMSs as a form of 2FA. Apparently this is not entirely safe.