I had the same problem. While logging in, I always got the message "Failed to verify your identity. try again". I faced this problem many times. And it was resolved automatically within 3-4 hours. I think it was a bug of Apple. But last time I couldn't log in for 1 week and couldn't update my apps. Then I clicked "Forget password" and Apple asked me for "Apple ID" and "Registered mobile number" and then locked the account. After 1 day Apple approved my request and then I was able to log in with my previous password. Hope this helps for you. Thanks.