You have not stated which operating system you are using but guessing its raspbian and Jessie full or lite.
If this is correct you should not be editing "/etc/networks/interfaces" any more to set static IP address you should now be using "/etc/dhcpcd.conf"
you should return your interfaces file to how it was before you edited it and then make the changes in dhcpcd.conf
a google search for "static ip jessie" will generate plenty of results but just in case here's one such result
https://pi-hole.net/faq/how-do-i-set-a- ... cpcd-conf/
and a post from this very forum