My model predicts 0 for all instances

class Net(nn.Module):
    def __init__(self):
        super(Net, self).__init__()
        self.fc1 = nn.Linear(30, 1)
        self.sigmoid = nn.Sigmoid()
    def forward(self, x):
        x = F.relu(self.fc1(x))
        x = self.sigmoid(x)
        return x
bobs_model = Net()
alices_model = Net()
bobs_optimizer = optim.Adam(bobs_model.parameters(), lr=args.lr)
alices_optimizer = optim.Adam(alices_model.parameters(), lr=args.lr)
models = [bobs_model, alices_model]
optimizers = [bobs_optimizer, alices_optimizer]
def update(data, target, model, optimizer):
    model.send(data.location)
    optimizer.zero_grad()
    prediction = model(data)
    print(prediction.view(-1))
    loss = F.binary_cross_entropy(prediction.view(-1), target)
    loss.backward()
    optimizer.step()
    return model

def train():
    for data_index in range(len(remote_dataset[0])-1):
        for remote_index in range(len(compute_nodes)):
            data, target = remote_dataset[remote_index][data_index]
            models[remote_index] = update(data, target, models[remote_index], optimizers[remote_index])
        for model in models:
            model.get()
        return utils.federated_avg({
            "bob": models[0],
            "alice": models[1]
        })
def test(federated_model):
    correct = 0
    total = 0
    federated_model.eval()
    test_loss = 0
    for data, target in test_loader:
        output = federated_model(data)
        test_loss += F.binary_cross_entropy(output.view(-1), target, reduction='sum').item()
        predection = output.data.max(1, keepdim=True)[1]
        # outputs = federated_model(data)
        _, predicted = torch.max(output.data, 1)
        total += target.size(0)
        correct += (predicted == target).sum().item()

    print('Accuracy of the network: %f %%' % (100 * correct / total))   
    test_loss /= len(test_loader.dataset)
    print('Test set: Average loss: {:.4f}'.format(test_loss))
for epoch in range(args.epochs):
    start_time = time.time()
    print(f"Epoch Number {epoch + 1}")
    federated_model = train()
    model = federated_model
    test(federated_model)
    total_time = time.time() - start_time
    print('Communication time over the network', round(total_time, 2), 's\n')