are you an insider? kindly join our forums so we could help you better.
in case you are an insider , your issue should be solved after a hard reset. to do hard reset using key combinations :
Turn off your phone.
Hold volume-down.
Keep holding volume-down and press power button for about 3 seconds.
Let go of the power button, but keep holding the volume down until ! image/icon on the screen appears.
are you using fast insider builds? The latest update has broken the pin lock so the only way is a hard reset or using windows device recovery tool
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