Total Beginner - Issue with FPS controller

Hi, I’m a complete beginner to coding and gamedev, and I’m following an introductory tutorial. In Unity 2023 I’ve tried two of the free FPS controllers. Unfortunately, most of the time the player character automatically moves forward and left, without any input from me. I’ve tried unplugging everything from my computer other than mouse and keyboard in case a peripheral was causing the issue, but no luck. Additionally, sometimes the FPS controller works fine the first time I run the game after I restart Unity, but then the second time I run it, the problem returns. Any idea what could be causing this? Thanks!

the automatic movement might be due to physics