How to edit thank you for subscribing email

Hi there, I set up my Hustle Pro embeds and slide-ins years ago, and I’m currently needing to edit the final email someone gets when they sign up for my email list using my Hustle Pro forms. I can’t figure out if the thank you email is something I set up in my Hustle Pro or if it is in Mailchimp (which I have integrated with Hustle Pro), I can’t find this email to edit it in either Hustle Pro or Mailchimp, I’m hoping you can help me remember where I set that up when I set up my Hustle Pro embed. Thank you!

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