Procedure Correction..Pls Help

Hi, I have this following procedure and I am sure on how to convert a part of the procedure. Can anyone pls help....
The function is created successfully. I have problem in calling that function n the procedure..Some syntax error...
I think, the problem is here...
UPDATE signoff SET user_name_assigned = getUserGroupName_upg(signoff_assigned_rec.user_ass igned) WHERE id = signoff_assigned_rec.id
-----------------

CREATE FUNCTION getUserGroupName_upg
(
@userId INT
)
RETURNS varchar
AS
BEGIN

DECLARE @temp varchar(520)
DECLARE @tmp_first_name varchar(520)
DECLARE @tmp_last_name varchar(520)
DECLARE @cnt INT
SELECT @cnt = COUNT(*) FROM agileuser WHERE id = @userId
IF ( @cnt = 1 )
BEGIN
SELECT
@tmp_first_name = first_name,
@tmp_last_name = last_name
FROM agileuser WHERE id = @userId
SELECT @tmp_first_name = RTRIM(@tmp_first_name)
SELECT @tmp_last_name = RTRIM(@tmp_last_name)
SELECT @temp = @tmp_first_name
IF ( @temp is not null )
BEGIN
SELECT @temp = @temp
END
SELECT @temp = @temp + @tmp_last_name
END
IF ( @cnt = 0 )
BEGIN
SELECT @cnt = COUNT(*) FROM user_group WHERE id = @userId
IF ( @cnt = 1 )
BEGIN
SELECT @temp = name FROM user_group WHERE id = @userId
END
END
return @temp
END
GO

-- Processing user assigned field of signoff table
DECLARE @signoff_assigned_rec VARCHAR(200)
DECLARE signoff_assigned_csr CURSOR FOR
SELECT id, user_assigned FROM signoff WHERE user_assigned is not null
OPEN signoff_assigned_csr
WHILE (0 = 0)
BEGIN --(
fetch NEXT FROM signoff_assigned_csr INTO @signoff_assigned_rec
IF (@@FETCH_STATUS = -1)
BREAK
UPDATE signoff SET user_name_assigned = getUserGroupName_upg(signoff_assigned_rec.user_ass igned) WHERE id = signoff_assigned_rec.id
END --)
close signoff_assigned_csr
DEALLOCATE signoff_assigned_csr
GO