When you tell the driver that your UAV is in fact a static piece of data ( original poster code ), and then try to write it, you gonna have trouble
D3D12_DESCRIPTOR_RANGE1 descriptorRanges[3];
descriptorRanges[0].RangeType = D3D12_DESCRIPTOR_RANGE_TYPE_UAV;
descriptorRanges[0].NumDescriptors = 1;
descriptorRanges[0].BaseShaderRegister = 0;
descriptorRanges[0].RegisterSpace = 1;
descriptorRanges[0].Flags = D3D12_DESCRIPTOR_RANGE_FLAG_NONE; // Should be at least DATA_VOLATILE, possibly DESCRIPTOR_VOLATILE
descriptorRanges[0].OffsetInDescriptorsFromTableStart = D3D12_DESCRIPTOR_RANGE_OFFSET_APPEND;