Re: Phone doesn't work after restore
If it was Verizon that told you to do a restore, it's their problem now. Bring the phone in to them.
If not, and the phone is still under warranty, it's still their problem. Bring the phone in to them. Doing a factory restore
does not void the warranty, it's a user function.
If not, flashing the stock ROM should fix it. Download
Kies - Windows and MacOS, go to
SamMobile Firmwares and download the image for your particular model number phone (not "S3", but "N7100", or whatever phone you have), find the file for Verizon and download it. Run Kies, go to Tools and there's an update item. Update the phone. (If there's no Verizon file,
do not use the file for another carrier. That can turn your phone into a box of useless parts.) You can still go to Verizon and see if they'll reflash the phone for free, or for a small charge - if you don't want to do it yourself, or you can't find a file to do it with.
And in the future, don't listen to anyone but Verizon, so if it doesn't work, they have to fix it. (Any time you talk to anyone at Verizon, record names, times and dates. Even if it's in the store. If someone in the store told you something, that's Verizon telling it to you. When you later tell them that Mary, on this date, at this time, told you to do that, you'll have a much stronger case than "someone here told me to do this about a month ago".)