If you own the account but forgot the password, use the Apple iForgot Portal to reset your password and regain access.
remove Activation Lock; it will re-trigger the lock screen upon setup. Do you have the original proof of purchase or contact with the previous owner to try the official unlock method? How to remove Activation Lock - Apple Support
There is no magical, free, one-click software that will remove the lock on 9.3.6 without some form of interaction with Apple or advanced hardware manipulation.
Would you like help with recovering an Apple ID or contacting Apple Support for an old device?
icon next to your network name and select "Forget this Network." Enter DNS: icon again. Select "Configure DNS" and choose Add Server: