mixed content error https

Hello,

I’m getting an error with my site being changed from http to https:

Mixed Content: The page at ‘https://www.mysite.com/’ was loaded over a secure connection, but contains a form which targets an insecure endpoint ‘https://mysite.us7.list-manage.com/subscribe/post?u=xxxxxxxxxxxxxxxx’. This endpoint should be made available over a secure connection.

41(index):570 Mixed Content: The page at ‘https://www.mysite.com/’ was loaded over HTTPS, but requested an insecure script ‘https://downloads.mailchimp.com/js/jquery.form-n-validate.js’. This request has been blocked; the content must be served over HTTPS.

I don’t see anywhere in the plugin settings to change this. What do you recommend?

Thanks for your help with this.