problem while exporting from asp.net mvc to excell

Question

good morning everyone.

i am trying to export a table from my asp.net view to excel.

i used a method i saw in c-sharpcorner here.

 

the problem is when i export the document in excel file, the cells where the formulas are applied display like this:

   

#NOM?

 

so i have to click on the cell then press enter in the formula bar.

after looking for a solution in the web i didn't a correct one.

 

this what my code looks like for a cell: <td x:fmla="=SOMME(A1:A2)" ></td> 

 

thanks in advance