Issue with checkbox functionality

[flint shoal]

I am not able to figure out why clicking on my checkbox functionality is throwing error
https://scrimba.com/scrim/cvRyW4sK

[silent eagle]

Try inserting console.log(index) between the current line 25 and 26, and then try using the checkbox. This will give you a big clue as to what is going on here!

[tired root]

Check this scrim to see the working todo app:
https://scrimba.com/scrim/co23f4426bd8187a32f94865b
Here I have added a check to see if the item with the matching value property was found in the priorTodo array, and I have also added a value attribute to the checkboxes that is bound to the value property of the items in the list. This allows the handleCheckboxClick function to correctly identify the item to update when a checkbox is clicked.

[flint shoal]

Thanks, made some changes and fixed it.