Why does my LSTM model raise max_seq_length <= 0 when predicting with new input of same shape?

Even though your input shape appears correct, it could be:

• Empty input at runtime:
  
  

• The shape is correct but the actual length of the input sequence is 0 (e.g., shape=(1, 0)).
  
  

• This happens when you pass an empty list or array by mistake.
  
  

• Mismatched batch/sequence dimensions:
  
  

• You may be feeding (batch_size, features) instead of (batch_size, timesteps, features).
  
  

• LSTM expects a 3D tensor: [batch_size, time_steps, input_dim].
  
  

• Data preprocessing error:
  
  

• Padding/truncation step might have removed all tokens.
  
  

• Tokenizer or sequence preparation may result in zero-length sequences.
  
  

• Predict mode vs. training mode inconsistency:
  
  

• Training was done with sequences of certain length, but prediction is using inconsistent time dimensions.