Why is my iPad Mini not recognizing my Apple ID and password?

I have a iPad Mini which is not recognizing my Apple ID and password. Every time it is asking me to sign into Face Time which I never use at all. I have repeatedly set my Apple ID and password correctly but it is not recognizing it at all. I am not able to use my device at all. I request someone to guide me in this issue. I have a iPad Mini which is not recognizing my Apple ID and password. Every time it is asking me to sign into Face Time which I never use at all. I have repeatedly set my Apple ID and password correctly but it is not recognizing it at all. I am not able to use my device at all. I request someone to guide me in this issue.
