Change database collation and unlink any connection to the database to execute the operation

change_database_collation.sql

USE master;  
GO  

ALTER DATABASE DATABASE_NAME
SET SINGLE_USER WITH ROLLBACK IMMEDIATE;
GO 

ALTER DATABASE DATABASE_NAME  
COLLATE Latin1_General_CI_AS ;  
GO  
  
--Verify the collation setting.  
SELECT name, collation_name  
FROM sys.databases  
WHERE name = N'DATABASE_NAME';  
GO

ALTER DATABASE DATABASE_NAME SET MULTI_USER; 
GO