sc_error_message doesn't show on mobile browser

I created a new project and security module.
Under the app_form_add_user, onBeforeInsert event, there is the following default codes
if({pswd} != {confirm_pswd})
{
sc_error_message({lang_error_pswd});
sc_error_exit();
}
{pswd} = md5({pswd});

I tried to run trigger the error on desktop browsers e.g. chrome, firefox, everything is fine. However on mobile browser it doesn’t show any error message and brings me back to the app_Login page. If this is a bug, do you know if there are any work around? Thanks.

sc version: 8.1.020