Pressing Shift+9 in Excel does not create a parenthesis instead

Pressing Shift+9 does not open parentheses when writing formulae instead it opens Ribbon Keyboard Shortcuts - Letters in small  images, key tips next to tabs-

Also I can type 1 2 3 4 5  but typing six...nine produce space not number.

 the only way I can open parentheses is to use the screen keyboard. anyone has a solution