Standard completion cards, conditional cards, score cards and badge cards are completion cards, and it is not possible to add a follow-up card after a completion card.
When a completion card is added, it is automatically located at the end of your mini-course and cannot be relocated. Even if you add another card chronologically after a completion card, it is located before the completion card.
If you want your mini-course to continue, even after a completion card, you can do it by adding links to your Standard & Score cards.
Create a mini-course, which will serve as the rest of your content after a score card. (You can name this course: “Let’s Continue!” or “Part 2”)
Go back to your main mini-course. Add a link to the completion card in the form of “Mini-Course” not “URL”.
Add the “Let’s Continue” mini-course to your score card.
You can find a detailed tutorial, here.
Note: This method works only for mini-courses that end with a standard completion & score card, as you cannot add links to conditional and badge cards.