Finetuning BART model by fariseq cannot generate more than 155 characters and end of the sign "�"

[AlexNLP]

🐛 Bug

To Reproduce

I used the BART model Finetuned by fairseq to conduct a machine transaction task, but the trained model cannot generate more than 155 characters, and the end of the sign "�", why is the output generated by the trained model so strange?

I guess the BART model can only embed 1024 tokens, so more than 1024 tokens cannot generate. A loose guess, Hope the answer please.