Authentication failure/////Access denied

I use WinSCP script to get data,whose name comprise of timestamp. But unfortunately, I am restricted at the very first while authenticating.
Here my script that i use
while i use this at line 3, i get a prompt "Too many arguments"
when i replace it by just then "password= " prompt is highlighting,but after giving password ,i get the tag like "KEYBOARD INTERACTIVE AUTHENTICATION , ACCESS DENIED". then prompt for password needed is showing again,but don't log in.

I have some queries::::::::
1.Can i use generated key by Puttygen function as hostkey ,Here i use it.
2.Can i use any user rather than root,Here i don't use root.

Is there a space in your password? What version of WinSCP are you using?

Please attach a full log file showing the problem (using the latest version of WinSCP).

There is no Space in password,But of course there is "@" sign, Will this create any trouble.
When i use the hostkey option,as i said previously,i get tag like "Too many arguments in open command".then abort.

You need to URL-encode the @.
See https://winscp.net/eng/docs/session_url

Here,I use The Encoded format of "@",in my Password field,But problem exists.

Here,I use The Encoded format of "@",in my Password field,But problem exists.

Checking the log file, your problem has nothing to do with the password. You do not even pass a hostkey verification. The reason is that you are using an ancient version of WinSCP (4.0.5 - 8 years old!) that does not support the -hostkey switch (let alone the %TIMESTAMP% syntax).

Here i Use the Latest version of WINSCP,At last authentication by hostkey has been successfully done But,while giving the password, it tells that access is denied.(Keyboard interactive authentication)
Here even i use encoded form of Special character in password field.then what will be the probable cause???. i share the log file.
Even Password is correct and same Password is used in another automation script for downloading data by FTP script.

In the latest version of WinSCP you can use /loglevel=* command-line switch to enable password logging, so you can check if correct password is used.