When you have problems like this, use block "print" to check if the code is being run like you think it is. For example, you can add at the beggining of when updated event: "print right as a text", then start the game, open console and see if it shows left after you pressed left. If it is still printing "false", then you know this part of your code works well and something must be wrong later. Remember to delete or deactivate print block afterwards, or it can really slow your game down.