When you first connect Katana to Xero, you'll be asked to map Xero ledger accounts and taxes to Katana. After this initial connection, there is no Xero configuration section in Katana that you can access.
If you want to change the integration configuration and re-import customers and suppliers, you'll need to disconnect your Xero account from Katana and reconnect. Katana remembers your previous settings, so all of your mappings will be prefilled when reconnecting. You can edit these mappings as you progress through the connection flow.
When the reconnection is complete, your Xero integration settings will be updated.
Reimporting customers and suppliers from Xero
In the last step of the setup, if you selected to import all your customers and suppliers, then all contacts are re-synced with data from Xero.
What is updated in Katana:
Customer: First Name, Last Name, Company Name, All Shipping address details, All Billing address details, Phone number
Supplier: First Name, Last Name, Phone number