Actually, no, your invoke order seems to be working too - I tried your code with toy inputs and it is learning ok.
You should check if regression can learn anything from your dataset, try this:
model = torch.nn.Sequential(
	torch.nn.Linear(inputSize, outputSize),
)
model._modules['0'].weight.data.zero_()
model._modules['0'].bias.data.zero_()
lossFn = nn.CrossEntropyLoss()
optimizer = torch.optim.Adadelta(model.parameters()) #Adadelta requires no lr tuning