chart months in English

[john_cash]

Hello,
in the attached workbook in the graphic sheet_ABCDE there are 2 buttons.
button 1 to display in chart 1 only the months of the table
button 2 to return to normal view (every month)
I don't understand why after clicking on button 1 and then in the
button 2 the months in the graph all months are displayed in English.
Now I don't know if those who try the file and have the English version can see the months in Italian.
A greeting
john