close javascript alert inside an iframe (but the alert is called in the main html)

[matheusvianaultralims]

I saw some solutions for modal next, but I got this code, it doesn't work and I really don't know how I can do this

My code:

Cypress.Commands.add("enterToCollectPointPage", () => {
  cy.get(".fa-users").click({ force: true });
  cy.contains("a", "Gerencia Proposta").click({ force: true });
  cy.get("iframe")
    .its("0.contentDocument")
    .its("body")
    .within(() => {
      const proposalIdPart = proposalId.split(".")[0];
      cy.get(
        `a[href*='../control/propostaControl.php?action=detalhaProposta&ai_Proposta=${
          proposalIdPart || mockNumber
        }']`
      ).click({ force: true });
      cy.get("#DadosPropostaNegocioEnsaio > .botoes > .click").click({
        force: true,
      });
      cy.wait(500);
      cy.get("#DadosPropostaNegocioEnsaio > .botoes > .click").click({
        force: true,
      });
      cy.get("#select2-ai_EnderecoColeta-container").click({ force: true });
      cy.get(".select2-search__field")
        .click({ force: true })
        .type("serv{enter}"); //colocar endereço de teste aqui
      cy.get("#ai_ContatoColeta").select(1);
      cy.get("#select2-ai_DescricaoAmostra-container").click({ force: true });
      cy.get(".select2-search__field").type("Água teste 001{enter}"); //digita o nome da matriz
      cy.get("#select2-ai_OrigemAmostra-container").click({ force: true });
      cy.get(".select2-search__field").type("a{enter}"); //digita o nome da origem amostra
      cy.get("#select2-ai_Legislacao-container").click({ force: true });
      cy.get(".select2-search__field").type("portaria{enter}"); //digita o nome da legislação
      cy.get("#select2-ai_ClasseLegislacao-container").click({ force: true });
      cy.get(".select2-search__field").type("Água Bruta{enter}"); //digita o nome da classe da legislação
      cy.get("#descricaoPontoColeta").type("teste");
      cy.get(
        "#cadastroPontoColeta > table.filtro > tbody > tr > td > img:nth-child(8)"
      ).click({ force: true });
      cy.get("div.principal > form > div.botoes > input:nth-child(5)").click({
        force: true,
      });
      cy.wait(1000);
      cy.get("div.principal > form > div.botoes > input:nth-child(5)").click({
        force: true,
      });

      cy.get("#select2-idEnsaio-container").click({ force: true });
      cy.get(".select2-search__field").type("teste{enter}"); //digita o nome do ensaion

      cy.get(
        "#cadastroEnsaioProposta > table.filtro > tbody > tr > td > img:nth-child(2)"
      ).click({ force: true });

      // cy.get("html").then((iframe) => {
      //   const body = iframe.contents().find("body");
      //   const win = iframe[0].contentWindow;

      //   cy.stub(win, "alert").as("windowAlert");

      //   cy.wrap(body)
      //     .find("#alert")
      //     .click()
      //     .should(function () {
      //       expect(this.windowAlert).to.be.calledWith("Hello world!");
      //     });

      //   // Após interagir com o iframe, sair dele e acessar o documento principal
      //   cy.window().then((win) => {
      //     // Fechar o alert diretamente no contexto da janela principal
      //     cy.stub(win, "alert").callsFake(() => {}); // ou fazer qualquer outra interação necessária
      //   });
      // });
    });
});