You can still take part in the defense next year, because there will be a chance to make up the exam within one year, and other results will be left to you. For example, if you took 1 1 month, you can choose to take any make-up exam in May next year and 1 1 month.

It's best to use the original, because you are familiar with the content, as long as you correct the shortcomings.

Of course, you can also use a new paper, but you should pay attention to the mistakes you made in your previous paper to avoid repetition.