I'm getting a shit load of 429s.
Slow down there fella and increase the speed setting... to something like 1000.
Or maybe primedice is just lagging...Not that it matters it still makes the bets despite any such errors.
I tried up to 3500, it stills fails to make proper betting, but the website is experiencing some problems, even automatic better doesn't work properly.
Its only part 2 of the tutorial just bare minimum interaction, it should be betting fine but you wont see new bets show up in your "my bets" unless you refresh the page.(If it doesn't work still id sugguest switching to firefox, as its the only browser i concern myself with while coding it)