Your access to the website should be updated the moment you become my patron, but this has failed in the past, and the system falls back to updating every 6th hour. Give it a couple of hours, but also please look at possible reason #2:
Whatever the reason, the problem is the plugin on these forums updates your patron/not-patron status immediately, so once you cancelled your Patreon pledge these forums think you are no longer a patron. It’s a bit stupid, but it is what it is.
… is fortunately easy! You need to re-activate your Patreon pledge while you download. If you’ve already paid this month, you won’t get charged again for this month!