Buyer Messages Different Username than Order?

[cks_cropper]

I've noticed this a couple of times now whereby when a buyer messages post-purchase that their username is slightly different on the message than what is on their order. How do you reconcile this? And why is this caused?

For the majority, it's kind of obvious as there is a very minimal change so you can make a fairly solid assumption who is asking the question. But the eBay system is awful when it comes to matching the two up. 

Am I missing something blindingly obvious here?

i.e. I've had a recent encuiry from an apparent purchaser, yet when I search in eBay under the Sold page, I cannot find this username against any of the orders. 

What is the best way to deal with this issue? The apparent buyer has failed to provide an Order Number (still awaiting response....) so just doing a post here in case I'm missing something. 

[john1297576 · Accepted solution]

Reply to the effect that as you have no record of a sale to their ID have they made a mistake.

NEVER get into conversation with other that the BUYER ID you have.  For all you know you could be being set up for a scam. Only the buyer can open a case so I can think of NO good reason to contact you using a different ID.

[cks_cropper · Accepted solution]

Thanks for confirmation. They have provided a valid Royal Mail Tracking ID which has helped to find the parcel has been sat at their local depot for almost a month and the customer hasn't re-arranged delivery/collection. Looks like they contacted me via a different product listing, which was confusing, and the name in the 'Sold' part of eBay is "Buyer: First Name Last Name" yet when you hover over that name, it shows you the actual eBay UserID which is different. Guess I'll have to view the HTML Source Code to find the usernames if this ever happens again. It's a bit of an annoying feature in the Sold page on eBay that this doesn't list the username too as it makes things hard to find.