Facing two years prison, I'm not guilty of entering with a key (6)

I believe the answer is:

typing

I'm a little stuck... Click here to teach me more about this clue!

'key' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Perhaps there's a link between them I don't understand?

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for typing that I've seen before include "Keyboarding" , "Using one form of keyboard" .)

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.