Why does not the registration on netflix work?

I use netflix on my phone and the account is from a friend of mine but the problem is that I can't log in to other devices on netflix and there's always the password specified is wrong, although it is correct. Can someone help me?

Could be because that has already logged in the maximum number of devices. For example, For the most expensive subscription, 5 devices can log in.

IQ is not! Read the text in the question again, and think about your answer