SQL Server Trigger Variable scope - sql

Question

Could you please tell me what's wrong this this trigger (below is just a portion of the trigger).
When put variable on where parameter I don't get any result, instead, when I set is a default value I get correct result
Like this it doesn't work (I verified and #Cont_local is not null and data really exists inside the database):
Note:
info (information) is in a different table but on the same database.
the trigger is set to work on Cont (Contact) Table
select #Cont_local = ContID from inserted
SET #Addr = (select Addr from Info I where I.ContID = #Cont_local)
But like this, it works
select #Cont_local = '454877'
SET #Addr = (select Addr from Info I where I.ContID = #Cont_local)
While #Cont_local is returning some values, the select statement cannot detect it.
Is this related to the scope of #Cont_local variable or something else?
Instead, when I try to put data manually, query return values and store it on #Addr
Here is Complete code
ALTER TRIGGER [dbo].[Insert__]
ON [dbo].[Cont]
AFTER INSERT
AS
BEGIN
DECLARE #Cont_local nvarchar(50);
DECLARE #Name nvarchar(50);
DECLARE #firstnameme nvarchar(50);
DECLARE #Addr nvarchar(50);
select #Name = contName from inserted
select #firstname = contfirstname from inserted
select #Cont_local = ContID from inserted
SET #Addr = (select Addr from Info I where I.ContID = #Cont_local)
INSERT INTO Final_Contact (Name, firstname, address) values
(#Name, #firstname ,#Addr)
END

Answer 1

select #Cont_local = ContID from inserted
This line of code works only when in the inserted-table is only one record

Answer 2

This addresses the original version of the question.
I don't see why your code would return an error. However, it is malformed and an error waiting to happen. Let me explain.
This code:
select #Cont_local = ContID from inserted
Assumes that inserted has one row. Of course, the code runs when inserted has more than one row. It just returns one value.
The inserted and deleted views in SQL Server triggers can refer to multiple rows. In other words, triggers are set-based processing rather than row-by-row processing. In a properly structured trigger, the references should always be in FROM clauses.
The following example is totally made up, but it illustrates how to update a column in another table using information from inserted:
update a
set addr = c.addr
where inserted i join
info i
on i.contid = a.contid join
addresses a
on a.addrid = i.addrid