MacBook doesn't want to unlock System Preferences

First off, what is the need for AntiVirus software on macOS. The OS is secure enough without adding a piece of software that interferes with the OS. Antivirus, Disk Cleaners, Optimizers are ti=ottaly unnecessary and can actually cause more harm that what they purport to do even to the extent of corrupting the OS. Suggest removing it via the Software developers instructions asap.

If you can't unlock settings in System Preferences - Apple Support

First off, what is the need for AntiVirus software on macOS.

Good to see you were eventually given credit for the best overarching answer.

Thank you @ Barney-15E