Welcome to our UiPath Forum! 
A couple of things:
-
please use the full address of Orchestrator in your Robot window:
That entire bit:
Into here:
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please make sure that your Orchestrator instance has the licenses assigned from your Cloud Account
And maybe a third thing - the latest version of Robot is this one:
You can get it from here: UiPath
And give it a fresh install as per this guide here:
How to fix your Studio installation / Licensing issues
Please also carefully follow the guide on how to connect your Robot to Orchestrator here: