sequenceDiagram
    actor Customer
    participant Store
    participant Payment
    participant Orders
    Customer->>Store: Confirm cart
    Store->>Payment: Request payment
    alt Payment approved
        Payment-->>Store: Approval
        Store->>Orders: Create order
        Orders-->>Store: Order number
        Store-->>Customer: Confirmation
    else Payment declined
        Payment-->>Store: Decline
        Store-->>Customer: Retry payment
    end