In respect to Veeam forum rules, please include your support case ID when posting about any technical issues. This will help to facilitate the extensive investigation and allow us to keep an eye on it.
To expand a bit on the error you received, it basically means that an object requested by the service is not present or available. This is a generic error which can be caused by a variety of different reasons (issues with proxy connection, repository, the object itself, etc.), which is why I'd kindly ask you to proceed to work with support engineers.
Are you facing a similar issue? If so, please contact Veeam Support for a cumulative patch, which can help you resolve this. And please take a minute to post your case ID in this thread.