This requires disassembling the laptop. If done incorrectly, you can permanently damage the motherboard.
The HP ProBook 440 G6 is a reliable business laptop, but forgetting the BIOS Administrator password (also known as the "Power-On" or "System Password") can turn the device into a brick. Unlike clearing a CMOS battery on a desktop, modern HP laptops store passwords in a non-volatile EEPROM chip, making a simple battery pull ineffective. hp probook 440 g6 bios password reset
Small Phillips screwdriver, tweezers or a paperclip, anti-static wrist strap (recommended). This requires disassembling the laptop