Touch id iphone 5s failed
Hello , i have an iPhone 5S , and i have a problem with Touch ID.
When i had iOS 10.2.1, Touch ID wasn't even showing in settings , it said only passcode , and since i updated to iOS 10 , Touch ID appears in settings , but when i want to turn on iPhone Unlock or iTunes&AppStore and put my finger , it says "Failed , Unable to complete Touch ID setup.Please go back and try again." and i tried a lot of times and still not working..
Can you please help?