From our current class link/classID -> Scammer just change a random number and then can easily join different classes

This cause security problem for our client since the account has added students as friends, sent inappropriate pictures/messages, entered an ongoing class and turned on the camera -> appeared without clothing

Change the ClassID/Class link format to include both digits and characters

for example: https://share.classin.com/s/a/?cid=zxes234