Hello Riya,
I think it will be better for you to continue with the old syllabus since you are already familiar with the old syllabus and have also studied for the same.
Switching for the new syllabus means you will again have to take all the tuitions and notes, which will be very cumbersome in my opinion.
so it's better to put all the efforts into the existing syllabus and try to clear the exam.
Also, if that's not what you wish to do, compare the changes that have been introduced and see if the new syllabus has topics from your comfort zone or the subjects you like, compare and see the pros and cons before making a final decision.

Hope this helps,
Good Luck!