Managing customers
Creating and editing customers, and the uniqueness rules.
User guide
Creating and editing customers, and the uniqueness rules.
The customer directory is business-wide — one record per person, shared by every store, with their contact details, address, notes and tags, and their order history behind it.
Who can do this: the Admin fully; Store Admins can view, add and edit; a Cashier can look customers up and add walk-ins at the till, but not edit or delete.

A customer needs a first name and at least one way to reach them — an email or a phone number. Both contact fields are unique across your business: a duplicate email or phone is refused on the spot, which is what keeps one person from becoming three records. Row click opens the profile read-only; Edit info opens it editing.
Two optional flows on top:
Deactivate is the everyday off-switch: the customer stops being recognised at checkout, stays on every record, and can be reactivated any time.
Delete is permanent — and refused for anyone with history. The dialog explains it honestly when the refusal comes back: "has order history, so deleting them would leave orders, invoices and refunds pointing at a customer that no longer exists. Deactivate them instead." Only a customer who never traded can actually be deleted.