Where did you try and reset your password? If you have already gone to the site https://iforgot.apple.com/password/verify/appleid and entered your apple id and continued to follow the onscreen instructions with an option to reset the password ***** either email, text, etc, then were you able to complete the process?
If you were able to complete the reset password ***** see if you can sign into https://appleid.apple.com/. This will show if your apple id account is ok and active with the new password. Then, if your apple id account is ok and you are able to sign in, then we can work on getting your iPhone working with the apple id and password.
Once we get to this point, I would make sure you are signed out of all your apple devices and computer, even itunes store, ect.
Then once you are signed out of all your devices you can then go back to the website https://appleid.apple.com/ and when signed in, look under devices and see if there is anything listed. If all is good then go ahead and first sign into your iphone 6 and see if it works this time.
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