Hi Ti, welcome to JavaRanch!
Sorry to hear about your failure. I'm sure you'll get it next time.
From
Oracle's FAQ
Retake Policy
Candidates must wait 14 days before retaking a failed proctored exam. (Registration will be allowed on the 14th day)
Candidates may retake an online non-proctored exam at any time.
Candidates may not retake a passed exam at any time.
Candidates may not retake a beta exam at any time.
Also, yes, I'm afraid they make you pay the fee again.
It's been awhile since I got certified, but I believe the score report still breaks down how well you did in different areas. Focus your study on areas where you did poorly, and that should give you the extra
boost you need succeed next time.