SQL Server: Unable to restore Database, Database is in use by session

You need to kick all the users out, and make sure you're not in that database too. Assuming you're in Management Studio, you need to change your context to a different database (or switch the database dropdown to a different database) this way, and this will also kick out any other users (which could be you - Object Explorer, Object Explorer Details, other query windows, etc. could all be inadvertently preventing the restore by maintaining a connection to your database):

USE master;
GO
ALTER DATABASE AMOD SET SINGLE_USER WITH ROLLBACK IMMEDIATE;

Once you've finished restoring and the database is ready for use again:

ALTER DATABASE AMOD SET MULTI_USER;