The fingerprint option disappeared from the settings.How to fix it?

@vikashkujur two reasons why this can happen. First may be due to Xiaomi’s software problems. Xiaomi has a lot of bugs on MIUI and have previously managed to disable the reader, through a firmware update that was pushed out.

Of course, there is also the possibility of a hardware problem. If your reader has failed, your phone will automatically remove it as an option in your settings.

I would start off with a factory reset. Make sure that you back-up your phone since you will lose your files (pictures, etc.) Also, and this is really important, make sure that you do know the proper password for your account. You will need all of that to reset and log back into your phone.

Should that not work, it may be time to replace the fingerprint reader flex. Use something like this video to replace it. Replacement flex cables are readily available. Do an online search to find a vendor you prefer.

While you work on your Poco X3 Pro, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has the same problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!