Can't do student log in.
I have created a course in Botany in Moodlecloud.com as per your instructions. I have 2 students enrolled. I am admin as well as the teacher's role is assigned to me. I can log in as an Admin user as well as a teacher. Priya Sinha is enrolled as a student for the course which is visible in participants list.
Moodle-Learning-Management-System Course-Administration-in-Moodle 12-13 min 40-50 sec
Please check the password for the student Priya Sinha.
You have to remember the login id and password for all enrolled users.