okay did this

philsbeasts-Pro:~ philsbeast$ \rm -f -/.ssh/known_hosts
rm: illegal option -- /
usage: rm [-f | -i] [-dPRrvW] file ...
       unlink file
philsbeasts-Pro:~ philsbeast$
\rm -f ~/.ssh/known_hosts

note not -

\rm -f ~/.ssh/known_hosts

it worked thanks here is a merit