Who I have the same questioned this topic

I recently unlocked an AT&T Iphone to use as my phone on Verizon. I have requested it to be unlocked and upon restoring the device through iTunes, it confirms that it is unlocked with a "Success! Your Iphone has been unlocked!' message.

However, when I try to switch my device by first adding the IMEI number for the phone, an error appears saying that the device is not compatible with the Verizon Network.