Different IMEI

there are different id's; IMEI, UDID, Serial number

But there should only be 1 IMEI

 

did you buy it new?

 

Ok that would mean that the box is not the original box that came with the phone, if they are both different

 

or the box and the sim-tray/body is original, but motherboard is swaped.

 

that might be common if you are not living in US

your motherboard or something else would be replaced in order for the iphone to be unlocked for non-US countries' SIM cards

 

Well, that's a load of ….

Unlocks are through an Apple database, it is controlled by IMEI number.
Apple can lock or unlock any iPhone, has nothing to do with hardware.

 

LMAO
Yeah ok.
In order to unlock an iphone you need to replace the Motherboard?
Where do people come up with stuff like that....