Opened the D3D12nBodyGravity project in VS and ran with F5 and saw this error in output window:
D3D12 ERROR: ID3D12CommandQueue::ExecuteCommandLists: Resource(0x000002AFEFEED460:'m_particleBuffer0[0]') (subresource : 0) was bound as DATA_STATIC on Command List 0x000002AFEB7B5C70:'m_commandList', still in execution (ExecuteCommandLists) by Command Queue 0x000002AFEB6BA200:'m_commandQueue'. It is invalid to change it until the command list has finished executing for the last time, but there is a state transition to (0x40: D3D12_RESOURCE_STATE_NON_PIXEL_SHADER_RESOURCE) here, which indicates a change to its data (or possibly resource metadata). [ EXECUTION ERROR #1002: DATA_STATIC_DESCRIPTOR_INVALID_DATA_CHANGE]
Opened the D3D12nBodyGravity project in VS and ran with F5 and saw this error in output window: