Hiw to Hack a Backend Server to Reach the Database??

So I have a database login credentials and it i know that it is being queried by a java web app through a client login page, what I want to do is to access directly to the database with the login and password I have, I know that they are correct because they are dumoed in a config.ini file on the server I am attacking, so perhaps the DBase prevent remote access I may try pivoting technique but I want 5o know why is the backend server login page just refresh without an error when I try to login even with wrong details inserted in login and pwd ??