Activation Lock
I have an iPhone 6s for 2 years and I forgot my apple id so when my little sister tried wrong passcode many times my device disabled, I tried to restore it with iTunes and when it worked I forget my apple id to activate it , by the way I bought my iPhone from someone on eBay and I don't have a contact with him anymore so I don't have a proof of purchase to ask him for , what can I do now ???
iPhone 6s