How do I correctly shutdown a derby database?

Question

I have a JavaFX application which uses an embedded database to store all data. Establishing a connection and inserting data works just fine besides the column 'id' auto incrementing by 100 instead of 1. I've read(Wrong auto increment in embedded Derby/ Java DB) that I have to shut down the database properly by using following code in my main class:

@Override
public void stop() {
    try {
        DriverManager.getConnection("jdbc:derby:"+"db"+";shutdown=true");
    }
    catch (SQLException sqlException){
        sqlException.printStackTrace();
        System.out.println("Database shutted down...");
    }
}

However it's still incrementing by 100 and I'm not sure why.

My code for establishing a connection and doing inserts:

try {
        Connection connection = DriverManager.getConnection("jdbc:derby:db");
        connection.setAutoCommit(true);
        System.out.println("Connection established");

        PreparedStatement preparedStatement = connection.prepareStatement("INSERT INTO orders(order_name, order_date, price) VALUES (?, ?, ?)");
        preparedStatement.setString(1, "TestOrder");
        preparedStatement.setDate(2, Date.valueOf(LocalDate.now()));
        preparedStatement.setDouble(3, 1.1);

        preparedStatement.execute();
        preparedStatement.close();
        connection.close();
    } catch (SQLException throwables) {
        System.out.println("Unable to establish connection");
        throwables.printStackTrace();
    }

And my SQL statement to create the table

DROP TABLE orders;
CREATE TABLE orders(
order_number  INTEGER PRIMARY KEY NOT NULL GENERATED ALWAYS AS IDENTITY(START WITH 1, INCREMENT BY 1),
order_name VARCHAR(100),
order_date DATE,
price DECIMAL(4, 2));