How do I get activation lock off my iphone5

You have no option other than to contact the original owner and ask them to unlock it. Only they can unlock the phone. They must remove the device from their Apple ID. Activation Lock is no joke and cannot be bypassed, not even by Apple.

Return it for a refund. Unless you can contact the original owner so that they can remove the Activation Lock, you will not be able to ever use it.

Sorry,

GB