How to fix "There is already an object named ... in the database" error?

Question

Database

Wrote the first script for MS SQL Server.
The first time I launched it - it worked fine.
Now I get the error "There is already an object named ... in the database".
Script:

-- начинаем работать в контексте системной базы данных [master]
USE [master]
GO

-- если база данных [dbRBL] уже существует, уничтожаем ее
IF EXISTS (SELECT name FROM sys.databases WHERE name = N'dbRBL')
DROP DATABASE [dbRBL]
GO

-- создаём базу данных [dbRBL]
CREATE DATABASE [dbRBL]
GO

-- переходим в контекст созданной базы данных [dbRBL]
USE [dbSPJ]
GO

-- создаём таблицу читателей [R]
CREATE TABLE [dbo].[R] (
[Rno] [int] IDENTITY(1,1) NOT NULL,
[Rname] [varchar](100) NOT NULL,
[Rsex] [varchar](10) NULL,
[Rbirthday] [date] NULL,
[Rphone] [varchar](30) NULL
)
GO

-- создаём таблицу книг [B]
CREATE TABLE [dbo].[B] (
[Bno] [int] IDENTITY(1,1) NOT NULL,
[Bname] [varchar](100) NOT NULL,
[Bauthor] [varchar](100) NULL,
[Byear] [date] NULL,
[Bpages] [int] NULL,
[Bweight] [int] NULL,
[Bcopies] [int] NULL
)
GO

-- создаём таблицу библиотек [L]
CREATE TABLE [dbo].[L](
[Lno] [int] IDENTITY(1,1) NOT NULL,
[Ladress] [varchar](150) NOT NULL,
[Ldate] [date] NULL,
[Lquantity] [int] NULL,
[Lphone] [varchar](30) NULL
)
GO

-- создаём таблицу записей
CREATE TABLE [dbo].[RBL](
[Rno] [int] NOT NULL,
[Bno] [int] NOT NULL,
[Lno] [int] NOT NULL,
[RBLdate] [date] NULL
)
GO

Answer 1

-- switch to the context of the created database [dbRBL]
USE [dbSPJ]
GO
database name error.