Donut generate ONLY <s><s>...<s></s>

After training the model, I have a normal training and validation loss decreasing over each epoch, only to return during generation the same token: text_sequence: <s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s>...<s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s><s></s>

Edit: I solved it by using transformer version 4.40.2