Database Stuck In Single User Mode

I have a database that got set into single user mode. Unsure the reason or who might opened it. I am trying to reset it, but I am having problems. I am trying the following from http://www.kodyaz.com/articles/alter-single-user-multi-user-mode.aspx to kill the connections. So I can then switch it back to multiple users.

DECLARE @DatabaseName nvarchar(50)
DECLARE @SPId int

SET @DatabaseName = N'Works'
DECLARE my_cursor CURSOR FAST_FORWARD FOR SELECT SPId FROM MASTER..SysProcesses WHERE DBId = DB_ID(@DatabaseName) AND SPId <> @@SPId

OPEN my_cursor

FETCH NEXT FROM my_cursor INTO @SPId

WHILE @@FETCH_STATUS = 0
BEGIN
KILL @SPId

FETCH NEXT FROM my_cursor INTO @SPId
END

CLOSE my_cursor
DEALLOCATE my_cursor

Which gives me the following error message when ran.

Msg 170, Level 15, State 1, Line 13

Line 13: Incorrect syntax near '@SPId'.