If you're adding a new staff member and you get the following error - Email has already been taken, another user is already using this email address in Tanda:
Check under Staff and Former Staff that you haven't already added this staff member previously in Tanda.
If you have, it's better to restore that employee than add a new record for them. Have a read on how to restore an in-active employee.
If no former staff are using the same email address, a current employee has the shares the same email address. Update the email address on their profile before entering in the email address into your new staff profile. No two staff members can share the same email address.
Note: If updating the email address for an existing user, notify them them of this change as they will need to use the updated email address to log into their account in Tanda.