Why do I get the error "Network input data format string cannot be empty" when using the "Predict" block in Simulink R2023b?

I have a network trained in PyTorch that I am importing into a MAT-file using the following code:

% Import network
net = importNetworkFromPyTorch("traced_net.pt");

% Initialize network
X = dlarray([1; 1; 1], 'CB');
net = initialize(net, X);

% Then, I save "net" into a MAT-file
I use this MAT file to import the network into the Deep Learning Toolbox "Predict" block to predict a certain input value. However, I am getting an error stating that the "Network input data format string cannot be empty", as seen in the image below:

What is the root cause of this error?