I have a Samsung A7100 and the pattern is locked. I have attempted many times to unlock it, but the new screen said to enter the username or password, but I don't know any account. Can you help me how to restore or reset my phone?
This phone can't be reset with the help of the volume buttons because it lacks a recovery system. You will need custom software and a hardware box that's able to reset it. You will need to visit a local phone service to reset the phone. It's very cheap and best of all, it preserves your data without wiping the whole phone.