First of all I'm not shore I can help. But I am having the exact same problem and know other people with the same problem. I am currently using the face unlock since the fingerprint unlock settings simply do not appear.
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Hey HEELSahil, I'm not a Professional at this or anything. But I have the exact same problems. Have you tried rebooting, the Phone or connecting it to your Mac or PC to do a software restart. You can try going in settings>Apps & notifications>App info, then click the 3 buttons in the top right corner and then click Show system. Then scroll down to find Fingerprints ASM & FingerprintExtensionService. Then click on both of them, select storage and then clear the cache. If that doesn't work clear the data. Try it for both Fingerprints ASM & FingerprintExtensionService. I tried this at first and it worked but then the problem arose, try this and it may work. You can also try booting it in safe mode by holding down the power button and HOLDING power off until it turns off. To get out of safe mode simply restart your device this won't delete any of your data. If this doesn't work I am not sure what else you can try. I have had this problem for the last few days and I am unsure why have you dropped or damaged your phone. I have not and this problem still persists. Hope you have better luck than me.
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