help activation locked

You acquired your device second hand from someone other than Apple or an authorized Apple reseller. The links below explain what has happened. You apparently didn't know to heed the advice given below.

Before you buy an iPhone, iPad, or iPod touch from someone other than Apple or an authorized Apple reseller, make sure that the device is erased and no longer linked to the previous owner’s account. 

And see: Activation Lock for iPhone, iPad, and iPod touch https://support.apple.com/en-us/HT201365 See

this heading Check for Activation Lock before you buy a device from someone else.

What all this means to you is that there is no way we can help you. We are not authorized to remove the activation lock from any device. And, under your circumstances, Apple will not help you since you cannot provide proof of ownership that Apple will consider to be sufficient. You would need to be the original owner and have your purchase receipt with the device's serial number on it. 

All I can suggest is that you try to recovery the needed password or the purchase price from the person you acquired the iPad from. Recovering the password is the only way the phone can be made functional for your use.

There is no way to unlock unless the previous owner do it:

What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch