批处理:命令的语法不正确。

I recently started trying to make a "login" in bacth by using some variables and if statements. What happened is when I run this code in CMD and I try to log in without having made a username or password, it should bring me to the label "FAIL" but instead it gives me the error "The syntax of the command is incorrect." While this doesn't tell me what lines I messed up on, I think its finding a problem with the IF/ELSE statements in the "LOGIN" label. Have a look for me, see if you can figure out what I'm doing wrong.I recently started trying to make a "login" in