Answer:
No this has not happened to me.
Explanation:
It may be because their internet is unstable or because the settings is not to "save username and password." Either way, they should make a new account and try only to use it for school, because if you use it for anything else to many times and get reported, brainly will give you a warning and then kick you out of brainly. I think. It has never actually happened to me. The reason could also be because there are too many people on brainly. You can never be sure.