i need help i bought a used iphone 6 plus but activation is on and the phone is worthless help me plz apple

It requires the Apple ID and password of the previous owner. If you don't have it and cannot get it, then the device is useless to you. Return it for a refund if you can.

Find My iPhone Activation Lock

In the future check first before buying second hand: How to check for Activation Lock before buying a used iPhone.

If the seller can't or won't remove the lock, return it and get your money back. If you can't do that, turn it over to the police. It's probably stolen.

That is correct it is useless. There is nothing anyone here or at Apple can do to help.

Enjoy your brick shaped like an iPhone.

The ASC is all fellow users and not Apple employees, Apple does not participate here.

You need to get the help of the previous owner to remove the activation lock on that iPhone 6+. There is no way to use it without the user taking the lock off either directly from the iPhone or by logging in to their iCloud account and remove the device from there.