This is a very personal question that depends on many factors, such as your relationship with your ex, the reason for your breakup, your current emotional state, and more. Therefore, I can't tell you directly whether you should agree or refuse.
Still, I can give you some direction to think about. First, you need to think hard about whether your relationship with your ex is really worth salvage. If your breakup was due to some minor conflict or misunderstanding, and you both still have feelings for each other, it may be a good idea to start over.
However, if the breakup between you is due to some serious issues like cheating, betrayal, lack of communication, etc., then starting over can be more difficult. In this case, you need to think hard about whether you will be able to forgive the other person and whether you will be able to resolve these issues.
Also, you need to consider your current emotional state. If you already have a new lover or you're trying to get out of the shadow of a breakup, then you may need more time to deal with your emotional issues. In this case, it may be better to reject the ex's composite request.
Finally, you need to be clear about your wishes. If you're hesitant or unsure about your ex's request to reunite, then you need to think hard about how you feel. If you really want to get back together, then you can try communicating with your ex to see if you can rebuild your relationship. But if you're not sure or don't want to get back together, then you need to tell the other person clearly what you think and don't leave the other person hopeful.
In conclusion, this is a very personal question that requires you to think hard about your situation and make a decision on your own. Whatever decision you make, respect your feelings and don't go against your will.