Hi,
Please note, that the access token is provided by Instagram itself. Instagram Feed WD plugin uses it to get data from Instagram API. Unfortunately, the plugin cannot control the access token and related errors in Instagram API.
However, here’s a solution you can try. Instagram occasionally expires access tokens from time to time. So please try to revoke access of the plugin from here, and also reset your access token from Instagram Feed WD plugin.
Thanks! Have a great day!