Q: i bought a iphone5c on eBay and updated it now i cannot get back into iphone

There is nothing you can do. Try working with eBay to get a refund, though that may be hard after this long.

I'm afraid, as Meg ST._Clair said, there is NOTHING you can do now.  You can try the eBay Buyer Protection Plan route. but it has been some time since the purchase and my understanding is that eBay is very strict about the time limit when they will assist.

I know this is of little comfort but the next time before you buy a used iPhone you need to get the IEMI or Serial number and check it at:

https://www.icloud.com/activationlock/

And if the buyer won't give you those numbers, then walk away.

Excellent advice.