Hi Sir,
hope this email find you well.  Here is Crystal from Bizbee, 10 years professional experiences for iPhone Screens.
 
Do you meet this problem? When you replace iPhone X screen, the Face ID could not work.
Why Face ID could not work after replacing iPhone X screen?
It is the problem of the screen of you replaced?  No, here is the real reason for this problem:
1. Please make sure ear speaker flex cable must be 100% apple official original. Because this flex cable is with Encryption chip.
If the flex cable is not original, the face ID could not work.
2. If you replace the screen, any parts on the flex cable is damaged, the Face ID could not work
3. During the operation of screen repair, if dot matrix instrument into liquid, In the maintenance environment, there must be a liquid for cleaning, such as alcohol, on the table. We disassembled the dot matrix instrument and found that there are many small holes in the dot matrix instrument.
Once the small hole is blocked, the dot matrix cannot emit infrared light, causing permanent damage and unable to repair the Face ID function.
83.75How we could avoid and solve this problem?
1. Please be more careful if you replace iPhone X Screens, make sure the alcohol not into the front camera flex cable.
2. Please be more careful, don't damage the front camera flex cable.
3. If the flex cable damaged, you need to remove the Proximity sensor and Flood illuminator to a new cable, then Face ID could work.
NCC Screens for iPhone X/XS, MOQ: 20 pcs, delivery time (3-5 Days)
33.04$------ X NCC Incell
36.11$------ XS NCC Incell
79.14$-------X NCC Soft OLED
83.75$-------XS NCC Soft OLED
Positive Feedback for iPhone X NCC Screen
Plz leave my name "Crystal" in the "Agent" column when you register on our website www.bizbeewholesale.com/1000278D.html 
, then you can get VIP prices and services. If you need more support, pls feel free to contact me.
Warm welcome to feel free to contact me any time:
WhatsApp: 008618682112549
Skype: 519499160@qq.com
Kind Greetings
Crystal 
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