Firstly,
you should use proper indention(opening bracket, closing brackets) which helps us to understand the problem code better.
Second, your syntax for EL in JSTL expression is wrong,
EL evaluates the attributes stored in session scope and print it, if it unable to find it in the scope, it simply return
empty string, that's mean it prints nothing. So you can able to find out your problem now and Google about "How to check null objects using EL" for workaround.
HTH