Remove old nuget source for Avalonia
MODIFY
NuGet.Config
NuGet.Config
<packageSources>
<clear />
<add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
- <add key="avalonia-all" value="https://nuget.avaloniaui.net/repository/avalonia-all/index.json" protocolVersion="3" />
<add key="AvaloniaCI" value="https://pkgs.dev.azure.com/AvaloniaUI/AvaloniaUI/_packaging/avalonia-all/nuget/v3/index.json" protocolVersion="3" />
</packageSources>
</configuration>

Remove old nuget source for Avalonia