I did a factory reset on my iPhone 6s and I'm locked out of it? How do I figure out the activation lock?

I've been trying to figure this out for an hour now and came up with nothing.

Added (1). Yeah, I had bought another phone since I was locked out of my iPhone for a week with no idea how to get past it.

It can only be unlocked using the Apple ID and password that the phone is registered to and that put the lock on the phone in the first place. There's no reset that gets around it without the owner's Apple ID.

You're seeing iCloud lock. It is an anti-theft feature. You have an iCloud/Apple ID. In order to continue, you need to enter it. If you can't remember your password, you can reset it through Apple. They will send and an e-mail to your recovery e-mail account or answer your security questions. If you can't do either for whatever reason, you're out of luck.

You put in your Apple ID & password. That's it.

It's normally the same id and password as you use in the app store!

Activation lock
Is email customer set when first got the phone
Activation lock can be reset in 3 ways 1./ sending recovery text message to number linked with this email
2./ Answering secrete questions
Date of birth
2 x favourite question and answer
3./ Send recovery email to backup email set in the phone

Activation lock can't be removed by Apple as it has been set from customer and it is personal information