[help] ipad 3 can't be activated

[datmast]

Hi all,
I got an ipad 3 with cellular from eBay. It shown model A1430(wifi&gsm) and the seller told me that it was used with At&t.
But when I tried to activate it, I could not see the imei and activate it ( I have checked : find my ipad is off and not in blacklist).
When I went to the website
http://www.chipmunk.nl/klantenservice/applemodel.html
To check its serial found that it is ipad 3 verizon version and refurbished
Then, I tried to restore the ipad 3 CDMA firmware, but I could not do it
Please help me how to restore the right firmware for it
Thanks