New staff, drivers and customers are emailed an invite with a link to set their own password. Ask them to check their spam or junk folder and that the email address on their record is spelled correctly.
For staff, press Resend invite in their row on the Staff page. For drivers, use the Login details card on the driver's page. If email is not available, FleetKraft shows a temporary password on screen instead for you to pass on; they can change it after logging in. For customer portal logins, remove and invite the person again from Portal on the Customers list.