I can confirm the NuGet server is up and running and is delivering packages. Here are some things to check on your side:
1 - Make sure you're using the same credentials to connect to the server that you have a license with.
2 - Select the "Telerik source" from the drop down in the NuGet Package Manager and that you're spelling the search term correctly (I recommend only searching for "xamarin
Here's a screenshot of what I mean:
If you're not seeing any packages available when you select the "Telerik source" form the drop down, then something went wrong with your credentials. In this case, delete the Telerik Package Source and re-add it.
If after everything, you're still not seeing packages, open a support ticket here
so that we can investigate further. Support Tickets carry a guaranteed response from the support engineering team within the ticket's timeframe. We try to monitor public forums, but this is limited to available resources.
Lance | Tech Support Engineer, Sr.
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