This error message is only visible to WordPress admins

Warning: The account for needs to be reconnected.
Due to Instagram platform changes on March 2, 2020, this Instagram account needs to be reconnected to allow the feed to continue updating. Reconnect on plugin Settings page

Error: Access Token for is not valid or has expired. Feed will not update.

There's an issue with the Instagram Access Token that you are using. Please obtain a new Access Token on the plugin's Settings page.
If you continue to have an issue with your Access Token then please see this FAQ for more information.