I also had this issue. I had to close all the instance windows that I had open, then close the RPA desktop design studio [save your design first], then open your instance, then open the design studio [you should have set up the auto login if you were following the lab]. Now click "connect to instance" it should show you it is already connected. This is not accurate, however. The connection times out, but it still shows as connected. Click the 'publish' button, even if you have already published. If you are actually connected, it will verify the connection and prompt you to enter a name or update an existing robot. Just cancel. If you still have issues connecting, Alphonsa has the right idea to check permissions. Make sure you are trying to connect to the correct instance, check the URL and correct password.
