> ## Documentation Index > Fetch the complete documentation index at: https://apidocs.noyax.com/llms.txt > Use this file to discover all available pages before exploring further. # Sub-records > Rules for addresses, telephones, links, representatives, bank accounts, group memberships and parameters. Customer sub-records can be managed in two ways: * **When creating a customer**: with the lists in the `POST /customers` body, in the same operation as the customer. If any record is invalid, the customer is not created either. * **Afterwards**: with each sub-record's own endpoints (`/customers/{customerId}/addresses` and so on). They support list, get, create, update and delete. [Update customer](/en/v1/customers/update) does not change sub-records; use their own endpoints. If the customer is not visible to the user, all sub-record endpoints return **404**. Sub-record updates are **full replaces**: fields you do not send are cleared. ## Addresses `/customers/{customerId}/addresses` | Field | Rule | | ---------------------------- | ------------------------------------------------------------------------------------------------------------------------ | | `DistrictId` | **Required.** An ID from the [district list](/en/v1/definitions/districts/list). City and country come from the district | | `Address` | **Required.** Street address | | `PostalCode` | Postal code | | `IsInvoiceAddress` | Whether this is the invoice address | | `CoordinateX`, `CoordinateY` | Location coordinates | `FullAddress` in responses is the address combined with district, city and country, and is read-only. ### Invoice address rules A customer always has **exactly one** invoice address. * **When creating a customer** with a single address, that address becomes the invoice address. With several addresses, exactly one must have `IsInvoiceAddress: true`. * **When adding an address**, the customer's first address always becomes the invoice address. A new address added with `IsInvoiceAddress: true` becomes the invoice address and the previous one loses the flag. * The flag of the invoice address **cannot be removed** by an update, and the invoice address **cannot be deleted**. Mark another address as the invoice address first. ## Telephones `/customers/{customerId}/telephones` | Field | Rule | | ------------- | ------------------------------ | | `Number` | **Required.** Telephone number | | `NumberType` | `1` Landline, `2` Mobile | | `Extension` | Extension number | | `Description` | Description | ## Links `/customers/{customerId}/links` | Field | Rule | | ------------- | ----------------------------------------------------------------------------------------------------------------------------- | | `Value` | **Required.** E-mail address or URL | | `LinkType` | `0` Other, `1` E-mail, `2` Website, `3` LinkedIn, `4` Instagram, `5` X. For type `1` the value must be a valid e-mail address | | `Description` | Description | ## Representatives `/customers/{customerId}/representatives` | Field | Rule | | --------------------------- | ----------------------------- | | `FullName` | **Required.** Full name | | `Position` | Position | | `Email` | E-mail. Must be valid if sent | | `Gsm`, `Phone`, `Extension` | Mobile, landline, extension | | `Link` | Link (e.g. LinkedIn profile) | | `Description` | Description | ## Bank accounts `/customers/{customerId}/bank-accounts` | Field | Rule | | ------------------------- | -------------------------------------------------------------------------------- | | `BankName` | **Required.** Bank name | | `CurrencyId` | **Required.** An ID from the [currency list](/en/v1/definitions/currencies/list) | | `Iban` | IBAN | | `Branch`, `AccountNumber` | Branch and account number | | `Description` | Description | Send either `Iban`, or `Branch` together with `AccountNumber`. ## Group memberships `/customers/{customerId}/group-members` | Field | Rule | | --------------- | ---------------------------------------------------------------------------------------- | | `GroupDetailId` | **Required.** ID of a detail from [customer groups](/en/v1/customers/definitions/groups) | * A customer can be a member of the same group detail only once. * Some groups may be defined as **mandatory**. When creating a customer, at least one detail from every mandatory group must be sent. This is checked only on create, not when a membership is deleted. ## Parameters `/customers/{customerId}/parameters` | Field | Rule | | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `ParameterDefinitionId` | **Required.** An ID from [customer parameter definitions](/en/v1/customers/definitions/parameter-definitions/list). A definition can be used once per customer | | `Value` | **Required.** Format depends on the definition type | | Type | Meaning | Example `Value` | | ---- | ----------------------- | ----------------------- | | `0` | Text | `"Priority"` | | `1` | Yes/No | `true` | | `2` | Integer | `12` | | `3` | Decimal (dot separator) | `12.5` | | `4` | Date | `"2026-09-17"` | | `5` | Time | `"14:30"` | | `6` | Date and time | `"2026-09-17T14:30:00"` | In responses, `ParameterType` is the definition type and `Value` is the value in that type's format. ## E-invoice labels E-invoice labels (GİB mailbox aliases) cannot be sent through the API; they are read-only. Send `QueryEInvoiceLabels: true` when creating a customer to query the labels from the e-invoice integrator by `TaxNumber` after the customer is saved: * Labels found are saved, and the first one is marked as default. * If the query fails, **the customer is still created**; labels stay empty. Labels are returned in `EInvoiceLabels` of [Get customer](/en/v1/customers/get).