Copying users from 3.8 to 4.3

I built a new shop based on nop 4.30 on a different server, and now i want to import old customers into new shop. I can't use upgrade script, so i studied the database relations and wroted  special program that export user data from old database and importing data into new database. Everything works well, I can see and edit every user data from admin panel but imported user login fails because of wrong password. Is there a some differences between nopcommerce versions`and password hashing algorithms?

In the General Settings > Security section, there is a field for "Encryption private key".  (Get it from your old site)

(In 'All settings', it's  securitysettings.encryptionkey)