Connecting AI agent to a sql server tool

Hi guys,
I’m a completely new in n8n and I want to use it to connect to my SQL server database and getting data using chat. but apparently it doesn’t understand what I want. I give it a query like below:
SELECT
au.UserName,
tu.FirstName,
tu.LastName
FROM TaskCatalog.Users tu
JOIN AspNetUsers au ON tu.UserId = au.Id
WHERE (tu.FirstName COLLATE Persian_100_CI_AI LIKE N’%{{ $json.input }}%’
OR tu.LastName COLLATE Persian_100_CI_AI LIKE N’%{{ $json.input }}%')
ORDER BY tu.FirstName
and it works when I use it in SSMS but in n8n it doesn’t.
this is what I made:


what I need is talk to my agent and get what ever data I want. but it doesn’t give me even data using my query