If you are using private feed then make sure you have installed this;
I ran this command in powershell (admin mode);
iex ((New-Object System.Net.WebClient).DownloadString('https://raw.githubusercontent.com/microsoft/artifacts-credprovider/master/helpers/installcredprovider.ps1'))
I have to run this command to restore packages;
dotnet restore –interactive
This command will open up a window and ask you to login to Microsoft website with a code. Login to https://microsoft.com/devicelogin and enter the code. This will do some sort of IDE verification. Close VS and reopen. You should be able to see all of your custom and nuget packages restored.
I found this alternative today;
dotnet restore projectName
This will restore the packages.
Close and restart VS. Hopefully this will restore the packages
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