Pubudu,
This is not unexpected. Because the exam is changing in March there are hundreds, even thousands more people trying to get their exam completed. Unfortunately you only have two options:
1.) Go back to the website every single day (maybe even multiple times per day) to see if someone has cancelled so that you can take their spot.
2.) Check other testing centers in your greater area for a seat. This means that you may have to travel a longer distance to take your exam, but at least you found a seat for the exam.
