Congratulations on launching your course on Udemy marketplace. If you have notifications enabled in your Udemy account, you will receive notifications at enrollments. However, it may happen that the students enrolled and then returned the course shortly after that. That's the only reason, I guess, you see 0 students in your dashboard. However, to be doubly sure, please visit the 'revenue report' in your account to see if anyone requested a refund soon after enrolling.