Commented Unassigned: Password not valid [11]

Good morning,
I'm using this module in a DNN 7.3.4 version.
I tried to import some user and I flagged the "send email option" and "geenrate random password"; the system sends password that aren't working in some users.

I tried to import 6 users and i received 2 valid passwords and 4 not valid passwords.

Thanks in advance for support,
best regards
Comments: We have tried module on clear DNN 7.3.4 and new passwords work ok. Also we double checked code, it uses standard DNN method UserController.GeneratePassword(). If you can reproduce bug, it would be good to make WebEx or TeamViewer meeting to find bug.