Mailchimp Lock

Hi there I’m actually contacting you on behalf of my client 52 Lives. I asked them to purchase the Mailchimp lock plugin and it seemed to work fine for a while but now whenever anyone enters their email address they get the ‘whoops something went wrong’ message and are unable to download the files. Email addresses already registered to the list appear to be working fine though. Do you have any idea what might be going wrong please?

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