Old owner Apple id

You acquired your new phone second hand from someone other than Apple or an authorized Apple reseller. Unfortunately you were scammed into buying an iPhone that will be useless to you. You 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/HT201365See

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

 you will need to contact the previous owner to have them log out of iCloud or go to https://www.icloud.com/find/ My Phone and erase the device, then remove it from their account. If you can’t do that, the device is useless. 

Turn off Activation Lock - Apple Support.