Customer Application Update

### Update an existing customer application entity. **Available to:** All authenticated users **Environments:** Demo, Live **[Rate Limit](/overview/core-concepts/rate-limits):** No endpoint-specific limit Overwrite a `CustomerApplication` entity record. This is the generic entity-update operation — the request body is the full entity, including its `id` and all required fields, so fetch the current record with [`customerApplicationItem`](/api/rest-api-endpoints/users/customer-application-item) first and modify only the fields you intend to change. Required fields: `id`, `userId`, `accountType`, `legalStatus`, `startDate`, `applicationStatus`, and `archived`. Optional fields include `accountId`, `clearingHouseId`, `rejectReason`, `rejectDate`, `additionalNotes`, `autoApprovalType`, and `duplicate`. When `rejectReason` is `OtherRejectReason`, `additionalNotes` must be non-empty. See [`customerApplicationCreate`](/api/rest-api-endpoints/users/customer-application-create) for the enum values of each field. This endpoint updates the entity record only; it does not drive the application through the account-opening workflow. Applicant details, documents, and signatures are managed with the application-flow endpoints — [`submitApplicant`](/api/rest-api-endpoints/users/submit-applicant), [`submitCustomerApplicationDocument`](/api/rest-api-endpoints/users/submit-customer-application-document), [`prepareAgreementDocuments`](/api/rest-api-endpoints/users/prepare-agreement-documents), and [`signAgreementDocuments`](/api/rest-api-endpoints/users/sign-agreement-documents). A successful request returns the updated entity. **Common Failure Scenarios** - No accessible customer application exists for the supplied `id`. - A required field is missing from the request body. - `rejectReason` is `OtherRejectReason` without `additionalNotes`. - The caller does not have write access to the application. - The access token is missing or invalid (returns `HTTP 401`).