zammad/app/frontend/shared/entities/ticket/graphql/mutations/update.graphql

mutation ticketUpdate(
  $ticketId: ID!
  $input: TicketUpdateInput!
  $meta: TicketUpdateMetaInput!
) {
  ticketUpdate(ticketId: $ticketId, input: $input, meta: $meta) {
    ticket {
      ...ticketAttributes
    }
    errors {
      ...errors
    }
  }
}