400 users have been chosen for import. once I clicked import, site gone down. I contacted administrators and they said there is spamming suspension from your website, though I didn't fill the email address form so no email notification should have been sent. Why this happened?!
I am so sad about this because clearance could spend 24 hours and I should launch website tomorrow and I need to publicize and test website tonight!
https://wordpress.org/plugins/import-users-from-csv-with-meta/