Authentication failed multiple times

I’m using the official Mailchimp WordPress plugin, version 2.1.0. My Mailchimp account is connected and the signup form successfully adds new subscribers to my audience. However, the WordPress plugin constantly shows “Authentication failed” and “We couldn’t get your lists from Mailchimp.” I have reconnected my Mailchimp account multiple times, logged in again, and deactivated/reactivated the plugin. The connection appears as active in Mailchimp, and new test subscribers are successfully added. Is there an issue with the authentication token or the API request used to retrieve my audience lists?

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