Hello I am a beginner and I am using pytorch to implement LSTM model for classification. when running the model the loss values keep changing (Increase and decrease randomly). shown by the following graph. When I try to implement it by other frameworks like Keras using the same data the results are correct and the loss decreases with time.

I am using MSELoss function and following is my code for the LSTM class
class LSTM(nn.Module):
    def __init__(self, input_dim=272, hidden_layer_size=64, output_size=1,batch=64,n_layer=1):
        super().__init__()
        
        self.hidden_layer_size = hidden_layer_size
        self.lstm = nn.LSTM(input_dim, hidden_layer_size,batch_first=True)
        self.linear1 = nn.Linear(hidden_layer_size, 32)
        self.relu = nn.ReLU()
        self.linear2 = nn.Linear(32, output_size)
        self.hidden_cell = (torch.randn(n_layer,batch,self.hidden_layer_size).cuda(), torch.randn(n_layer,batch,self.hidden_layer_size).cuda())
        self.sigmoid = nn.Sigmoid()
        
    def forward(self, input_seq):
        lstm_out, self.hidden_cell = self.lstm(input_seq, self.hidden_cell)
        #print(lstm_out[:,-1,:].shape)
        linear1_out = self.linear1(lstm_out[:,-1,:])
        relu=self.relu(linear1_out)
        linear2_out = self.linear2(relu)
        prediction=self.sigmoid(linear2_out)
        return prediction
    
    def backward(self,g0):
        raise RuntimeError("Some Error in Backward")
        return g0.clone()