diff --git a/lib/embulk/input/jira_api/client.rb b/lib/embulk/input/jira_api/client.rb
index 839f0cc..876d2cc 100644
--- a/lib/embulk/input/jira_api/client.rb
+++ b/lib/embulk/input/jira_api/client.rb
@@ -41,7 +41,7 @@ def total_count(jql)
         end
 
         def check_user_credential(username)
-          Jiralicious::Issue.find(username)
+          Jiralicious::User.search(username)
         rescue Jiralicious::JqlError, Jiralicious::AuthenticationError, Jiralicious::NotLoggedIn, Jiralicious::InvalidLogin => e
           raise Embulk::ConfigError.new(e.message)
         rescue ::SocketError => e