This plugin is broken

It was working, not sure when it quit. Isn’t an issue with WordPress, but the plugin itself.

All information filled out (client, secret, etc). But using the widget doesn’t return any data, using the shortcode returns this:

Error: Missing access credentials. See https://developer.foursquare.com/docs/oauth.html for details.

https://www.ads-software.com/extend/plugins/foursquare-venue/