AuthenticationFailed in Capistrano

Hello friends!

I am getting following error while using
$ cap deplot:setup
* executing `deploy:setup'
  * executing "mkdir -p ~/public_html/simak-in
~/public_html/simak-in/releases ~/public_html/simak-in/shared
~/public_html/simak-in/shared/system ~/public_html/simak-in/shared/log
~/public_html/simak-in/shared/pids"
    servers: ["simak-in"]
connection failed for: simak-in (Net::SSH::AuthenticationFailed: mandy)

Please help me to solve this error?