Not found

At CreamCityCentral.com/instagram I’m trying to put together a feed, but it tells me to enter a User ID and Access Token. I go to the plugin page, click the button, get those numbers and past them into the right boxes. When I try to save it, it just goes to my site’s Not Found! page. It won’t be accessible for a couple minutes (we’re about to launch) but I want the feed up asap

https://wordpress.org/plugins/instagram-feed/