Hi!! thanks for playing the game!
What happened is that you didn't activate the circuit breaker in the basement, which is how I make the front door key spawn :p there was a both a visual bug and with the UI due to how close the circuit breaker and that last note are together that makes it confusing. If you want to play the game again, you can just go through to the basement, back off a little and go back towards the circuit breaker until the left click message pops up again. Should spawn the key and let you finish the game :)
Sorry about the bug! I'll get a fix running as soon as I have access to the files again.