How to solve Activation Lock for Iphone6

activation lock is not a thing on the iphone it's a theft protection on apples servers

it needs to be removed How to remove Activation Lock - Apple Support

if you don't know your appleID password If you have forgotten your Apple ID password – Apple Support (UK)

then you will need the assistance of apple Activation Lock - Support (apple.com)

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Apple Support

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Contact - Official Apple Support

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Genius Bar Reservation and Apple Support Options - Apple

If this is a second-hand phone, and it is locked to someone else. It will remain locked unless you can enlist the help of the owner. If the seller has “disappeared” or stopped responding to messages, this may indicate that you were scammed and are in possession of a possibly-stolen “brick”.

If you logged into the account of a scammer and they locked the phone, the phone is lost to you.