I don't know why I can do only this command alone without any error message:
alter database <dbname> set single_user with rollback immediate
drop database <dbname>
But when I add the redgate restore command after that, it should be message like:
user account do not have permission to alter database, user database can't be set in single user mode.
At the end, the DB can be store succesfully, any idea why so strange?