Hello raqib289,
It sounds as though you're having issues enabling Touch ID on your iPhone. Apple Support Communities is a great place for help! We do see that there is a related article to your post. Did you have the opportunity to complete the steps in that article? If not, complete the steps in the article as those are the recommended steps from Apple to help reach a resolution.
If you've already walked through those steps, or the issue continues after doing so the next step would be to contact Apple. You can find the available contact information for Apple via the Get Support website.
Take care!