deploying sim function

I believe neural network sim function is supported in deployment, but when I tried to deploy a function which uses a pre-trained network, it failed.

Here's what I have done:

1. Train a network 'net' and save it in 'testnet.mat'.

2. The code of 'test.m':

 %#function network
load testnet.mat;
net = network(net);
p = sim(net,[1]);

And I keep getting error message like:

No appropriate method, property, or field delays for class nnetWeight. MATLAB:noSuchMethodOrField

Please tell me what's wrong with my code or deployment.