I agree that can be odd. I made this decision to defeat bots that may be trying to fake their way in. Since it's only a 5-digit code it wouldn't take a bot long

I agree that can be odd. I made this decision to defeat bots that may be trying to fake their way in. Since it's only a 5-digit code it wouldn't take a bot long to guess the right code. By invaliding the code the first time a wrong one is used I think it makes bots very unlikely to guess correctly. I think. I hope.