Why is finger sensor doesn't work

@arsemashimekit there are a few different reasons why your fingerprint sensor my not work. Try the software solutions from the Samsung site first.

If those do not work, then it is possible that you may have a bad reader. Since iFixit does not yet a guide for that, use the one from here. The fingerprint sensor flex is readily available at many online stores. Do an online search for this and select a vendor that appeals to you.

While you work on your phone, 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.