SSH Between Host Not Working

I have server A and server B and can ssh from server A to server B if I'm logged in as the user whose keys have been set up

But, I can't do user@serverB from server A logged in as another user

and I can't do the following to allow the user to ssh to the local server

-bash-4.2$ ssh-copy-id jenkins@localhost
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
Permission denied (publickey,gssapi-keyex,gssapi-with-mic).

I'm lost