I assume the ebay seller didn't supply the original proof of purchase invoice @Geordiepete as the purchase date in on there. Maybe contact the seller and ask for a copy to be emailed which would also help if any warranty claim needs to be made in the future.
You could call Samsung Support and they'll check out the serial number to look at it's warranty status.
I maybe wrong but there isn't an official Samsung page where you can fill in your phone's details and instantly get this information.
Some information here samsung.com/uk/support/warranty/
There are 3rd party sites that require registration and the input of your phone's imei number but personally I wouldn't want to share that information online with such a site but that's my personal preference.
Daily Driver > Samsung Galaxy s²³ Ultra 512Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
