You have to click on the "get code" link in the game under whatever number it asks you for. It will take you to the patreon post with a certain date on it. You use that date with the chart that's linked on the front page of the game (the "patreon codes" one) and copy the number that it asks you for in the game i.e 0 or whatever it asks for. So if the link in the game takes you to September 22nd then you would find September 22nd in the chart and copy the code next to the number they ask you for. It's kinda complicated but that's always worked for me, sorry for the yapping, but I hope this helps
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