Recovery mode:
(power+ volume up+ home key)
- Hold the keys until you finally see the green Android screen.

Download mode:
(power+ volume down+ home key)
- Hold the keys until you see the download screen.

*the home key is the middle button below the screen.

 

First, let me say this...

DON'T BUY SMARTPHONES OFF EBAY!!!!1! ARE YOU CRAZY?!!!!!!!!11!!11!1!!!!!

lol, that out the way

The boot screen you described sounds like maybe cyanogen mod which is not officially supported on the phone. Honestly sounds to me like the seller installed a custom ROM and softbricked the device.

Either way, you've been had. File a report with Ebay and demand your money back. Then get your Ace 2 handset from a trusted retailer.

 

You're not likely to get much support for that as it sounds like (never heard of it myself) a replica phone made in china. Why on earth they'd bother to replicate the Ace 2 is beyond me but the problem is it would be hard to know what firmware it needs and what would work best.

Doing some research it seems the phone MIGHT be legit, but it also might not be. I cannot find ANY information on firmware however so it's very possible you're screwed. File a fraud complaint with EBay and request a refund.Assume your handset is a lost cause. I think that's the best thing to do. Doubt you'll get much more help here (at least in this section of the forums) as your phone is not a Samsung Galaxy Ace 2.