> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bolta.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Amend Tax Invoice - Cancellation of Contract

> For a "Cancellation of Contract" amendment, you pass only the single `date` (write date) field, and the original issued invoice is offset. Amendment is not possible if an item's supply cost on the original tax invoice is negative.

For details, see the [Amendment types guide](/en/api-introduction/amendment-guide).




## OpenAPI

````yaml /openapi.en.yaml post /v1/taxInvoices/{issuanceKey}/amend/termination
openapi: 3.1.0
info:
  title: Bolta API
  description: >
    The Bolta e-tax invoice API. [API Overview](/en/api-introduction/overview) |
    [Authentication guide](/en/api-introduction/authentication) | [Use
    cases](/en/api-introduction/usecase-b2b)
  version: 1.0.0
servers:
  - url: https://xapi.bolta.io
    description: Bolta API server
security:
  - basicAuth: []
tags:
  - name: Tax Invoice Issuance
    description: >
      Issue and amend e-tax invoices. [Calculating the issuance
      amount](/en/api-introduction/issuance-guide) | [Amendment
      types](/en/api-introduction/amendment-guide)
  - name: Tax Invoice Retrieval
    description: Retrieve e-tax invoice results and request processing status.
  - name: Reverse Issuance
    description: >
      Request and manage reverse issuance of e-tax invoices. [Email-approval
      reverse issuance](/en/api-introduction/usecase-reverse-email) |
      [Simple-approval reverse
      issuance](/en/api-introduction/usecase-reverse-simple)
  - name: Cash Receipt
    description: >
      Issue, cancel, and check the status of cash receipts. Issuance and
      cancellation are asynchronous. Check the final result via webhook or the
      status API. [Cash receipt guide](/en/api-introduction/cash-receipt-guide)
      | [Cash receipt webhooks](/en/api-introduction/webhook-cash-receipt)
  - name: Issuer
    description: >
      Register and manage businesses that act as tax invoice issuers.
      Certificate requirements depend on the issuance type.
      [Glossary](/en/api-introduction/glossary) | [Delegated
      issuance](/en/api-introduction/usecase-delegated) | [Brokered Tax Invoice
      Issuance](/en/api-introduction/usecase-brokered)
  - name: Certificate
    description: >
      Register and manage issuer certificates. [Certificate
      registration](/en/api-introduction/certificate-registration)
paths:
  /v1/taxInvoices/{issuanceKey}/amend/termination:
    post:
      tags:
        - Tax Invoice Issuance
      summary: Amend Tax Invoice - Cancellation of Contract
      description: >
        For a "Cancellation of Contract" amendment, you pass only the single
        `date` (write date) field, and the original issued invoice is offset.
        Amendment is not possible if an item's supply cost on the original tax
        invoice is negative.


        For details, see the [Amendment types
        guide](/en/api-introduction/amendment-guide).
      parameters:
        - name: issuanceKey
          in: path
          description: Issuance request identifier
          required: true
          schema:
            type: string
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                date:
                  $ref: '#/components/schemas/DateString'
                  title: Write date
                  description: Contract cancellation date
              required:
                - date
      responses:
        '200':
          description: ''
          content:
            application/json:
              schema:
                type: object
                properties:
                  issuanceKey:
                    $ref: '#/components/schemas/IssuanceKey'
                    description: The IssuanceKey of the amended tax invoice
                required:
                  - issuanceKey
          headers: {}
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '500':
          description: Internal server error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
      deprecated: false
components:
  schemas:
    DateString:
      type: string
      format: date
      examples:
        - '2024-08-24'
    IssuanceKey:
      type: string
      description: >-
        An identifier for the issuance request. Note that the format and length
        may change.
      examples:
        - 8D529FAD3EBAE050B79CE943CCC7CEDE
    ErrorResponse:
      type: object
      description: The error response returned when an API request fails
      properties:
        code:
          type: string
          description: Error type identifier
        message:
          type: string
          description: Error description
        traceId:
          type: string
          description: Request trace identifier
      required:
        - code
        - message
        - traceId
  securitySchemes:
    basicAuth:
      type: http
      scheme: basic
      description: >-
        Base64-encode your API key and pass it. Enter the API key as the
        username and leave the password empty.

````