Face id is not working plz repair my face id

You will have to contact the official Apple Support or an authorised Apple Service Provider about that.

Only specially trained technicians should repair this part of the hardware. Click on the blue link below as a fist step:

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Take your device to an Apple Store or Apple Authorized Service Provider, or contact Apple Support about your iPhone

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copied from: If an alert says Face ID has been disabled on your iPhone or iPad Pro - Apple Support