Mac brightness won't stay at 100%

My brand new MacBook Pro 16" that's running macOS Catalina 10.15.6, refuses to keep the brightness at 100% where I want it to be at all times. I have deselected "Automatically Adjust Brightness" from the Display settings. I have deselected "Slightly dim the display while on battery power" in the Energy Saver settings and it still dims to about 75% randomly throughout the day. When I leave and come back to my plugged in, fully charged MacBook Pro, somehow its at 75% brightness when I left it at 100% brightness. Please help!

Here are screenshots of my current settings: