stream motive data to simulink rigidbodydata empty

Hi,

After unsuccessfully trying to stream between Motive and Simulink (either iwth udp, or Or Hirshfeld solutions), I tried to use a wrapper to access to NET.addAssembly while running simulink.

So first if I want to get x position I have my wrapper:

function x = NatNet_wrapper(RigidBody_ID)

addpath('my path to dll')

dllPath = fullfile(my path to dll 'NatNetSDK','Samples','Matlab','NatNetML.dll');
assemblyInfo = NET.addAssembly(dllPath);
theClient = NatNetML.NatNetClientML(0) % Input = iConnectionType: 0 = Multicast, 1 = Unicast
HostIP = char('127.0.0.1');
theClient.Initialize(HostIP, HostIP) % Flg = returnCode: 0 = Success

frameOfData = theClient.GetLastFrameOfData()
rigidBodyData = frameOfData.RigidBodies(RigidBody_ID);

X= single(0);  
X = rigidBodyData.x;  
x = double(X)

Then I have a matlab Function in simulink:

function x = getoptitrackdata(RigidBody_ID)
%#codegen
coder.extrinsic('NatNet_wrapper'); 

x = double(0); 

x = NatNet_wrapper(RigidBody_ID);

When I run Simulink I can see in the diagnostic viewer that the flag Flg=0 so it's initialized, but I get

Struct contents reference from a non-struct array object.

error because my frameOfData is empty.

Do you have any why? I made sure streaming is on on motive and that my asset has the right index and is tracked.

I run matlab 2016b / on windows 64bits.

Any help would be great, Thanks