Bought a used iPhone but it has an activation lock

Hello ~ Well… in a word no we cannot and Apple cannot as well. You best option is to either return it to place of purchase for a refund or perhaps that person can remove the activation lock for you. If they cannot or will not…recycle the device responsibly. Take a look here for more info:

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

~Katana-San~

No one can help you except the person who enabled activation lock. Most likely you bought a stolen phone, and activation lock is doing its job of making a stolen phone unusable. See→The All Too Common SAD Reality of Buying a Used iPad/iPhone

As you know, you have run into the Activation Lock. This is a security feature to discourage theft and resale of the iPhone. The only way to remove the Activation Lock is to input the credentials that are requested. Those credentials are the Apple ID and Password of the original owner. Return the iPhone to the seller and get your money back because you are not going to be able to remove the Activation Lock without that information.

Axel F.