someone logged into my ebay account. Why would someone do that. What is the gain for them?

[secondtimetreasures]

I had a notice that someone had signed into my ebay account....and I think it was 2 different people cause it ws 2 locations.  What is the gain for someone to log into my account?

[eburtonlab]

Change your eBay password immediately if you think someone else knows it or is able to sign in to your account.

https://www.ebay.com/help/account/protecting-account/get-help-hacked-account?id=4196

Someone with access to your account may be able to make purchases and have you pay for them if you have a linked payment method that does not require another password to use, or can change your settings to have your future orders shipped somewhere else, or can list scam items in your name, or change your banking information so payments for your items go to someone else.

Check all your account details closely, particularly contact information, address, payment information.

Keep in mind that location information comes from the network provider used when signing in, so if you have been using a VPN or a hotspot, or certain kinds of privacy software, that can affect the location shown on the "new device" message.

[gosimus]

@secondtimetreasures 

< I had a notice that someone had signed into my ebay account >      

I get those, too.  I get them because I have my browser set to delete all cookies when I close an app.  Since eBay can't see a cookie (because it was removed) it "thinks" that somebody else is logging in.  I ignore them. 

I suspect that your notice(s) is for the same reason.  Or, if you're using a VPN, the same thing can happen, because the VPN makes your IP address appear to jump around all over the place.