Illustrator 2024 has a known issue where a saved file is automatically stored in a new folder. Cartoon Animator is unable to read the location of this folder and therefore loses track of the SVG file. Unfortunately, the only possible workaround is the revert back to Illustrator 2023:

1) Check the official Adobe site for ways to change your version of Illustrator.
2) Choose to install any minor version of Illustrator 27.xx.
3) Adjust the preferences in Cartoon Animator.

4) Update the path to Illustrator akin to “C:\Program Files\Adobe\Adobe Illustrator 2023\Support Files\Contents\Windows\Illustrator”.