Press and hold power button and both volume buttons to force reboot your device. After force reboot immediately press and hold hard reset combination buttons. it will take few attempts and then you will reach to recovery mode to wipe/factory reset your Samsung device.[br]
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If you have the Samsung device then after factory reset it will FRP Google account locked to unlock it follow this guidelines.
[link|https://www.deviantart.com/unlockerplus/journal/How-to-Bypass-Samsung-FRP-Lock-875794231|How to Bypass Samsung FRP Lock]