Confirmation message includes original text

Do sure if I have configured correctly, but my confirmation box is somewhat odd.

I have a basic box with text saying “Please sign up” below that is the form box with a place for the email.

On confirmation I still have the “Please sign up.” but the form box now has the thank you message.

It seems odd that the “Please sign up” message is still there. Can I load a separate box or remove the message somehow?

I am using Boxizlla and MC4WP.

Thanks

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