If used with an optional access token for an anonymous session, all Orders and Carts that belong to the anonymousId are assigned to the newly created Customer.
If omitted in the request body, the [Customer](ctp:api:type:Customer) `stores` field is set to the [Store](ctp:api:type:Store) specified in the path parameter.
A Cart returned in the [CustomerSignInResult](ctp:api:type:CustomerSignInResult) has any invalid Line Items removed and is [updated](/api/carts-orders-overview#cart-updates) with the latest prices, taxes, and discounts. During these updates, the following errors can be returned: [MatchingPriceNotFound](ctp:api:type:MatchingPriceNotFoundError) and [MissingTaxRateForCountry](ctp:api:type:MissingTaxRateForCountryError).
Creating a Customer produces the [CustomerCreated](ctp:api:type:CustomerCreatedMessage) Message.
If used with an optional access token for an anonymous session, all Orders and Carts that belong to the
anonymousId
are assigned to the newly created Customer.