I have reviewed the posts regarding this issue going back to May with no resolve.
The issues are that the setup connectivity for Sallie Mae back has the Password and User name fields reversed in the dialog box. You would think this is no issue, so you just put in your fields the opposite of every other dialog in Quicken banking setup (R65.17 - 27.1.165.17) and the connection will work BUT if you go to the password vault the User name displays the password instead and it can readily be seen in password vault instead of the user name. Will this ever be fixed?
You can refer to this closed thread about another user reporting this issue with no resolve.
Adding Sallie Mae Account is Broken — Quicken