Sometimes you may discover Telescope to not be available and the request timing out.
One of the reasons for this could be that Telescope is configured over the HTTPS protocol and you are using an HTTP protocol endpoint. This can be confirmed by looking at the start of the URL to check what protocol is being used. Since the protocols use different ports, a typo in this can make it seem like Telescope isn't available as the request won't be able to find the Telescope application.
Steps To Fix
Simply change the protocol and you should be able to reach the Telescope application.
Additionally, you can also set up forwarding for the unused protocol to forward all requests to the protocol over which Telescope is being served. OnDemand customers can raise a support ticket if they want a redirect configured.
If OnDemand customers want a redirect configured, raise a ticket on PLNP JIRA of type SaaS Request mentioning the customer name and the request.
Reload the page at the updated URL and Telescope should load.