"ctrl 2" not working

im am sending successfully
ctrl 1, ctrl 3, ctrl 4
to switch to a specific tab in chromium (kiosk mode) but
but ctrl 2 is not working

a online keyboard tester shows `<ESC>` instead of `<2>`

i tried
`wtype -M ctrl -k 2 -m ctrl`
and 
`wtype -M ctrl "2" -m ctrl`

(version-info: wtype is already the newest version (0.4-3+b1).