@sivakumarl, after carefully rereading the documentation on defining a custom manager agent, it’s clear that an agent is created, but this agent doesn’t have a task explicitly declared. My guess is that the system will internally construct the task for this agent, taking into account the details of the other agents. Also, you created a task called categorize_tickets, assigned this task to your manager agent, and also listed this task in the tasks parameter of your crew.
I suggest you follow the documentation, excluding the task manually assigned to your manager agent, and try your code again. If you succeed, please come back here and report it, so others can benefit from your progress.