Best Answer: To set up the phone again, you will need to have the Google credentials for the last user. Google has several tools that will help you retrieve your credentials if you forget them.
Google and the company who made your phone have tools that can help protect your privacy and prevent theft. Factory Reset Protection requires that you know your password and your Google account password in order to reset your device and make it work as new. What information do I need to have access to my old account information? All recent Android versions require that you use the same account password and account number to unlock your phone if it has been reset. It's called FRP, and it's used in order to make stolen phones less expensive. My phone cannot be unlocked if stolen. If it is reset through the phone's recovery menu, I will need my Google account details to do it again. The most valuable Android phones are highly valued. You're less likely than others to steal my phone if it's not in use. If you find a phone that you can't use, it's more likely you will turn it over to police. This feature is used by every company that makes phones that have access to Google Play. Some also have their own version that allows you to do the exact same thing through your accounts. It can be a bad idea if it prevents you from using your phone. To sync with Google's servers, the username and password of the last user on your phone may need to be known when you either reset it through the recovery menu or purchase a used phone with FRP activated. Although it should erase the account through the settings, it sometimes doesn't. Sometimes these details are forgotten, and if the phone was purchased from another person, it might not be possible to retrieve them. Although people continue to search for ways around the FRP lock, once they are found, they can be quickly patched. It's worth doing a Google search to find the patches, even though they may take some time to get through carriers and manufacturers. Reset your password
Source: Android Central
If this happens to your account and you have unmitigated access from another device (or tablet, or computer), your first instinct should be to reset your Google account password. After resetting your phone, if you have access to your account on another device that is not controlled by you, you can reset the password to gain access. There are some things that you should know. You might be restricted from using the new password for up to 24 hours on older phones. This is to prevent "suspicious activity" such as stealing someone's Google account password and changing it. Then, you might not be able to log into another device with the new password to harvest their data (banking details or financial details, like an Amazon account). After a password change, you will need to wait 24 hours before you can set up a Google account. This is a Google decision and not the company that created your phone. It is done with the best intentions and it's much better than having your bank account empty. What do I do if the password is not known?
Source: Android Central
There are three methods to gain access. You can only use the Google account recovery tool to access the first. You can follow this link to begin the recovery process if you have already done it. You should ensure that your phone is fully charged and switched on. Also, make sure that you have access to the recovery email or recovery number. Two-factor authentication requires that you have a way to authorize the account. The recovery tool will guide you through the steps to disable or use a CAPTCHA code. Next, you will need to reset your account password on another device. Wait for 24 hours (or 72 as noted above) before trying to set it all up. The phone can be left on or turned off while you wait. Otherwise, the countdown may reset. It's not worth the inconvenience of waiting for a day or three to get your account access and then not being able use your phone again. You will need to contact the original seller if you purchased used. You can also hack your way in. This is not something we recommend, but it might be a good option for someone who enjoys hacking on their phone's software. This could lead to serious problems if you get it wrong, and even cause the phone to malfunction. It's not an option that most people would choose. You can fill out this form, or call (650.253-0000) to get help. The company that you purchased the phone from may be able to help. If you don't know the owner of the account and are unable to access it, contact the company you purchased the phone from. This is the only way to avoid it. You will need to give the seller your password or refund your money. Set up account recovery options to prevent permanent lockout
Source: Jerry Hildenbrand/Android Central
You can save yourself future headaches by setting up your account recovery options once you are in. Add your account recovery options to your Google account sign in and security settings page. These options tell Google how to send a token to your account to allow you to access it if you are locked out. This will resolve all of the problems that can occur when FRP does not work correctly. We encourage you to provide as much detail as possible. Don't forget, the FRP "issue", even if it hasn't yet hit you, doesn't necessarily mean that it will. You don't have to worry about being locked out of your phone or your account. If you need help, Google will assist you.