How can I optimize my writetable function to run faster

I have a program that uses the import tool

It writes information from the import tool to a struct named myData

myData is then used to write the information from each cell into a spreadsheet with the information stored in a separate sheet in the excel file.

It takes a long time to run the program and was wondering if there is a faster way to call and write this information to excel.

for jj = 1:list
    store = myData{1,jj}
        
        un_in = unique(store)

writetable(un_in,filename,'Sheet',jj,'Range','A1');
end