Cant update fetch after some operation?

[gpbaculio]

This is my mockFetch:

global.fetch = jest.fn();
const mockFetch = global.fetch as jest.Mock;

Then inside it:

const iphoneHandlerRef = { current: false };
    mockFetch.mockImplementation((url, init) => {
      // Use the endpoint handlers approach
      const endpointHandlers = getEndpointHandlers(iphoneHandlerRef.current);
      const handler = endpointHandlers.find((h) =>
        h.match(url.toString(), init),
      );

      return Promise.resolve(
        handler ? handler.response() : mockResponses.default,
      );
    });

    const user = userEvent.setup();

    const { rerender, unmount } = render(<MockFlipSetup />);

   ...
    jest.restoreAllMocks();
    jest.clearAllMocks();

    iphoneHandlerRef.current = true;

    mockFetch.mockImplementation((url, init) => {
      // Use the endpoint handlers approach
      const endpointHandlers = getEndpointHandlers(iphoneHandlerRef.current);
      const handler = endpointHandlers.find((h) =>
        h.match(url.toString(), init),
      );

      return Promise.resolve(
        handler ? handler.response() : mockResponses.default,
      );
    });

    // Advance timers
    await act(() => {
      unmount();
    });
    // Rerender the component
    rerender(<MockFlipSetup />);

The fetch still returns the initialized response?