In order to hard reset a Gigaset GS370 Plus, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Gigaset GS370 Plus device will be brought back to the default configuration of a brand new device.
1. Power down the phone by pressing and holding Power.
2. Now press and hold Volume Up + Power buttons for a few seconds.
3. Release both buttons when Gigaset logo pops up.
4. Wait for the Android logo to appear and press Volume Up and Power buttons simultaneously.
5. Navigate to wipe data/factory reset using Volume and Power buttons.
6. Lastly, select Yes - delete all user data and reboot system now.
7. Well done, the hard reset process is over.