vi editor is not responding

Did you try ESC-colon-q-bang?

:q! 

ESC to get out of insert mode, colon is to enter command mode, 'q' to quit, the bang is to discard any changes. It looks like you may just be missing the colon for command mode.

Check out this post for other ways to exit vi: https://stackoverflow.com/a/11828573/2543416

I think you wanted to save the file with CTRL-s. That's a screen-lock. Use CTRL-q to unlock and save with :w.