According to repair experience, this case may be caused by an iPhone X baseband problem or an iPhone NFC circuit problem. Since the iPhone X works properly before recovery, so the iPhone X baseband should be fine, then we should pay attention to the NFC circuit.
First of all, we need to disassemble the iPhone X. Use screwdriver to remove the screws at the bottom of the iPhone display screen, put the iPhone X on the CPB screen separator, and then use screen pry tools and screen sucker to open the iPhone display screen.
Remove the iPhone X display assembly, disconnect the iPhone X battery, and then take off the iPhone X motherboard.
Put the iPhone X motherboard under a Black Trinocular Microscope to observe, the iPhone X motherboard looks good.
Place the iPhone X motherboard to the SS-T12A heating station to separate the iPhone X motherboard double layers, after heating for a while, use tweezers to take off the iPhone X motherboard upper layer.
Now we can see that a lot of pins have dropped, sign in to the ZXW online account to check iPhone X schematic diagram, those dropped pins are all related to the NFC circuit. Now we can judged that the iPhone X won't activate because the middle layers pins are dropped, we can reball it.
Once done, install these two layers with MJ CH5 heating station, and then assemble the iPhone X.
Connect the iPhone X to the computer, use iTunes to restore it again, and now the iPhone X can be activated successfully. Test the functions on the iPhone X, they all works well. The iPhone X activation problem has been solved!