MacBook Pro blackened display

Why my MacBook Pro's display blackened? It is not an old model (13-inch 2019, 2TBT3, serial number FV***412). I carried it to your repair team in APM Kwun Tong Hong Kong but they said they could not fix it after check with cause unknown. Now I can only use it on an external monitor via a HDMI cable.

I believe I am not the only one having this issue so that's why I want to raise the awareness to this platform. Thank you.

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