excel worksheet could not be activated. in matlab

main.m
% Create an Excel application object
e = actxserver('Excel.Application');

% Make Excel visible (optional)
e.Visible = true;

% Open a workbook
ewb = e.Workbooks.Open('C:\example.xlsx');

% Activate a worksheet
ews = ewb.Worksheets.Item('Sheet1');
ews.Activate;

% Do some operations on the worksheet
ews.Range('A1').Value = 'Hello, world!';
ews.Range('A2:A10').Value = pi .* (1:9)';
% ...

% Save and close the workbook
ewb.Save;
ewb.Close;

% Release the Excel application object
e.Quit;
delete(e);
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