Why does no key combination work to move to desktop (space) 11?

Shot in the dark and can not supply Apple Support Documentation to support - But there might be Limits on the number Desktops that the computer can have.

Am picking from memory having seen same question raised.

Perhaps More Learned Contributor(s) will pickup your question and supply more insights or documentation.

Whickwithy wrote:

I went to syspref>keyboard>shortcuts>mission control and changed "Switch to Desktop 11". No matter what key combination I choose, it will not go to desktop 11.

Perhaps because there is no "Switch to Desktop 11", only "Switch to Desktop 1".

Third time's a charm as they say. 😎